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1.
Ann Bot ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136192

RESUMO

BACKGROUND AND AIMS: Pollination failure occurs from insufficient pollen quantity or quality. However, the relative contributions of pollen quantity vs quality to overall pollen limitation, and how this is affected by the co-flowering context, remain unknown for most plant populations. Here, we studied patterns of pollen deposition and pollen tube formation across populations of four predominately outcrossing species in the genus Clarkia to evaluate how richness of co-flowering congeners affects the contribution of pollen quantity and quality to pollen limitation. METHODS: We partition variation in pollen deposition and pollen tube production across individuals, populations and species to identify the main sources of variation in components of reproductive success. We further quantify the relative contribution of pollen quantity and quality limitation to the reproductive success of the four Clarkia species using piecewise regression analyses. Finally, we evaluate how variation in the number of co-flowering Clarkia species in the community affects the strength of pollen quality and quality limitation. RESULTS: Across all contexts, pollen deposition and the proportion of pollen tubes produced varied greatly among individuals, populations, and species, and these were not always correlated. For instance, C. xantiana received the smallest pollen loads yet produced the highest proportion of pollen tubes, while C. speciosa exhibited the opposite pattern. Yet, co-flowering richness had variable effects on the strength of pollen quantity and quality limitation among populations. Specifically, breakpoint values, which are an indicator of overall pollen limitation, were two times larger in the four-species community compared with one and two-species communities for two Clarkia species, suggesting that pollen limitation can increase with increasing richness of co-flowering congeners. CONCLUSIONS: Our results reveal a complex interplay between quantity and quality of pollen limitation and co-flowering context that may have different evolutionary outcomes across species and populations.

2.
Surg Oncol ; 55: 102098, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38991627

RESUMO

BACKGROUND: Minimally invasive techniques have demonstrated several advantages over the open approach. In the field of prostate cancer, the LAP-01 trial demonstrated the superiority of robotic-assisted radical prostatectomy (RARP) over laparoscopic radical prostatectomy (LRP) when comparing continence at 3-month after surgery, with no statistically significant differences at 6 and 12 months of follow-up. OBJECTIVES: Externally validate the LAP-01 study and compare functional outcomes between the two minimally invasive approaches. MATERIAL AND METHODS: This retrospective study, conducted by a single surgeon (MRB), utilized data from a prospectively collected database, which included patients who underwent both RARP or LRP. Data regarding baseline characteristics, continence (assessed through the 24-h Pad test and ICIQ questionnaire) and potency were collected at multiple time points: 1 and 6 weeks after catheter removal, 3-, 6-, and 12-months post-surgery. RESULTS: The study encompasses 601 patients, 455 who underwent LRP and 146 RARP. The median age at diagnosis was 64 for LRP and 62 for RARP, while the median PSA levels at diagnosis were 6.7 ng/mL for LRP and 6.5 ng/mL for RARP. Bilateral nerve-sparing procedures were performed in 34.07 % of LRP cases and 51.37 % of RARP cases. RARP exhibited a significant advantage over LRP both in continence and potency. Continence rates at 3-, 6- and 9-month after radical prostatectomy (RP) were 36.43 %, 61.86 % and 79.87 % for LRP, compared to 50.98 %, 69.87 % and 91.69 % for RARP. Potency rates at the same intervals were 0.90 %, 3.16 % and 6.39 % for LRP, and 6.19 %, 9.16 % and 18.96 % for RARP. These rates were more pronounced in patients with bilateral nerve-sparing. CONCLUSION: Our study demonstrates that RARP results in significantly better continence recovery and superior potency outcomes throughout the entire follow-up period compared to LRP, even at the beginning of the robotic approach learning curve.


Assuntos
Laparoscopia , Prostatectomia , Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Incontinência Urinária , Humanos , Masculino , Prostatectomia/métodos , Prostatectomia/efeitos adversos , Laparoscopia/métodos , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Procedimentos Cirúrgicos Robóticos/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Incontinência Urinária/etiologia , Incontinência Urinária/prevenção & controle , Seguimentos , Complicações Pós-Operatórias , Idoso , Disfunção Erétil/etiologia , Disfunção Erétil/prevenção & controle , Estudos Prospectivos , Prognóstico
3.
Food Sci Nutr ; 12(7): 4513-4533, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39055196

RESUMO

Cancer is a major global health challenge that affects every nation and accounts for a large portion of the worldwide disease burden. Furthermore, cancer cases will rise significantly in the next few decades. The Food and Drug Administration has approved more than 600 drugs for treating diverse types of cancer. However, many conventional anticancer medications cause side effects, and drug resistance develops as the treatment proceeds with a concomitant impact on patients' quality of life. Thus, exploring natural products with antitumor properties and nontoxic action mechanisms is essential. Ginger (Zingiber officinale Roscoe) rhizome has a long history of use in traditional medicine, and it contains biologically active compounds, gingerols and shogaols. The main ginger shogaol is 6-shogaol, whose concentration dramatically increases during the processing of ginger, primarily due to the heat-induced conversion of 6-gingerol. Some studies have demonstrated that 6-shogaol possesses biological and pharmacological properties, such as antioxidant, anti-inflammatory, and anticancer activities. The mechanism of action of 6-shogaol as an anticancer drug includes induction of paraptosis, induction of apoptosis, increase in the production of reactive oxygen species, induction of autophagy, and the inhibition of AKT/mTOR signaling. Despite this knowledge, the mechanism of action of 6-shogaol is not fully understood, and the scientific data on its therapeutic dose, safety, and toxicity are not entirely described. This review article examines the potential of 6-shogaol as an anticancer drug, addressing the limitations of current medications; it covers 6-shogaol's attributes, mechanism of action in cancer cells, and opportunities for future research.

4.
Biomed Pharmacother ; 177: 117047, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38959604

RESUMO

Cancer remains a leading cause of death, with increasing incidence. Conventional treatments offer limited efficacy and cause significant side effects, hence novel drugs with improved pharmacological properties and safety are required. Silvestrol (SLV) is a flavagline derived from some plants of the Aglaia genus that has shown potent anticancer effects, warranting further study. Despite its efficacy in inhibiting the growth of several types of cancer cells, SLV is characterized by an unfavorable pharmacokinetics that hamper its use as a drug. A consistent research over the recent years has led to develop novel SLV derivatives with comparable pharmacodynamics and an ameliorated pharmacokinetic profile, demonstrating potential applications in the clinical management of cancer. This comprehensive review aims to highlight the most recent data available on SLV and its synthetic derivatives, addressing their pharmacological profile and therapeutic potential in cancer treatment. A systematic literature review of both in vitro and in vivo studies focusing on anticancer effects, pharmacodynamics, and pharmacokinetics of these compounds is presented. Overall, literature data highlight that rationale chemical modifications of SLV are critical for the development of novel drugs with high efficacy on a broad variety of cancers and improved bioavailability in vivo. Nevertheless, SLV analogues need to be further studied to better understand their mechanisms of action, which can be partially different to SLV. Furthermore, clinical research is still required to assess their efficacy in humans and their safety.


Assuntos
Antineoplásicos , Neoplasias , Triterpenos , Humanos , Animais , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Triterpenos/farmacocinética , Triterpenos/farmacologia , Triterpenos/química , Desenvolvimento de Medicamentos/métodos , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Benzofuranos
5.
Med Oncol ; 41(8): 186, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918260

RESUMO

This comprehensive review delves into the multifaceted aspects of genipin, a bioactive compound derived from medicinal plants, focusing on its anti-cancer potential. The review begins by detailing the sources and phytochemical properties of genipin, underscoring its significance in traditional medicine and its transition into contemporary cancer research. It then explores the intricate relationship between genipin's chemical structure and its observed anti-cancer activity, highlighting the molecular underpinnings contributing to its therapeutic potential. This is complemented by a thorough analysis of preclinical studies, which investigates genipin's efficacy against various cancer cell lines and its mechanisms of action at the cellular level. A crucial component of the review is the examination of genipin's bioavailability and pharmacokinetics, providing insights into how the compound is absorbed, distributed, metabolized, and excreted in the body. Then, this review offers a general and updated overview of the anti-cancer studies of genipin and its derivatives based on its basic molecular mechanisms, induction of apoptosis, inhibition of cell proliferation, and disruption of cancer cell signaling pathways. We include information that complements the genipin study, such as toxicity data, and we differentiate this review by including commercial status, disposition, and regulation. Also, this review of genipin stands out for incorporating information on proposals for a technological approach through its load in nanotechnology to improve its bioavailability. The culmination of this information positions genipin as a promising candidate for developing novel anti-cancer drugs capable of supplementing or enhancing current cancer therapies.


Assuntos
Iridoides , Neoplasias , Humanos , Iridoides/farmacologia , Iridoides/química , Iridoides/uso terapêutico , Neoplasias/tratamento farmacológico , Compostos Fitoquímicos/uso terapêutico , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Animais , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Apoptose/efeitos dos fármacos
6.
Ecol Evol ; 14(6): e11494, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855315

RESUMO

Land-use change is one the greatest threats to biodiversity and is projected to increase in magnitude in the coming years, stressing the importance of better understanding how land-use change may affect vital ecosystem services, such as pollination. Past studies on the impact of land-use change have largely focused on only one aspect of the pollination process (e.g., pollinator composition, pollinator visitation, and pollen transfer), potentially misrepresenting the full complexity of land-use effects on pollination services. Evaluating the impacts across multiple components of the pollination process can also help pinpoint the underlying mechanisms driving land-use change effects. This study evaluates how land-use change affects multiple aspects of the pollination process in common milkweed populations, including pollinator community composition, pollinator visitation rate, pollen removal, and pollen deposition. Overall, land-use change altered floral visitor composition, with small bees having a larger presence in developed areas. Insect visitation rate and pollen removal were also higher in more developed areas, perhaps suggesting a positive impact of land-use change. However, pollen deposition did not differ between developed and undeveloped sites. Our findings highlight the complexity evaluating land-use change effects on pollination, as these likely depend on the specific aspect of pollination evaluated and on the of the intensity of disturbance. Our study stresses the importance of evaluating multiple components of the pollination process in order to fully understand overall effects and mechanisms underlying land-use change effects on this vital ecosystem service.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38739152

RESUMO

As peptide-based therapies gain recognition for their potential anti-cancer activity, cyclic peptides like Sansalvamide A, a marine-derived cyclic depsipeptide, have emerged as a potential anti-cancer agent due to their potent activity against various cancer types in preclinical studies. This review offers a comprehensive overview of Sansalvamide A, including its sources, structure-activity relationship, and semi-synthetic derivatives. The review also aims to outline the mechanisms through which Sansalvamide A and its analogs exert their anti-proliferative effects and to discuss the need for enhancements in pharmacokinetic profiles for better clinical utility. An extensive literature search was conducted, focusing on studies that detailed the anti-cancer activity of Sansalvamide A, its pharmacokinetics, and mechanistic pathways. Data from both in vitro and in vivo studies were collated and analyzed. Sansalvamide A and its analogs demonstrated significant anti-cancer activity across various cancer models, mediated through Hsp 90 inhibition, Topoisomerase inhibition, and G0/G1 cell cycle arrest. However, their pharmacokinetic properties were identified as a significant limitation, requiring improvement for effective clinical translation. Despite its notable anti-cancer effects, the utility of Sansalvamide A is currently limited by its pharmacokinetic characteristics. Therefore, while Sansalvamide A exhibits promise as an anti-cancer agent, there is a compelling need for further clinical and toxicological studies and optimization of its pharmacokinetic profile to fully exploit its therapeutic potential alongside modern cancer therapies.

8.
Mol Nutr Food Res ; 68(8): e2400063, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38600885

RESUMO

Phenethyl isothiocyanate (PEITC), a compound derived from cruciferous vegetables, has garnered attention for its anticancer properties. This review synthesizes existing research on PEITC, focusing on its mechanisms of action in combatting cancer. PEITC has been found to be effective against various cancer types, such as breast, prostate, lung, colon, and pancreatic cancers. Its anticancer activities are mediated through several mechanisms, including the induction of apoptosis (programmed cell death), inhibition of cell proliferation, suppression of angiogenesis (formation of new blood vessels that feed tumors), and reduction of metastasis (spread of cancer cells to new areas). PEITC targets crucial cellular signaling pathways involved in cancer progression, notably the Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB), Protein Kinase B (Akt), and Mitogen-Activated Protein Kinase (MAPK) pathways. These findings suggest PEITC's potential as a therapeutic agent against cancer. However, further research is necessary to determine the optimal dosage, understand its bioavailability, and assess potential side effects. This will be crucial for developing PEITC-based treatments that are both effective and safe for clinical use in cancer therapy.


Assuntos
Isotiocianatos , Neoplasias , Isotiocianatos/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/farmacologia , NF-kappa B/metabolismo , Antineoplásicos Fitogênicos/farmacologia
9.
Phytother Res ; 38(6): 3169-3189, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38616356

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by the accumulation of amyloid-beta plaques and neurofibrillary tangles, leading to neuronal loss. Curcumin, a polyphenolic compound derived from Curcuma longa, has shown potential neuroprotective effects due to its anti-inflammatory and antioxidant properties. This review aims to synthesize current preclinical data on the anti-neuroinflammatory mechanisms of curcumin in the context of AD, addressing its pharmacokinetics, bioavailability, and potential as a therapeutic adjunct. An exhaustive literature search was conducted, focusing on recent studies within the last 10 years related to curcumin's impact on neuroinflammation and its neuroprotective role in AD. The review methodology included sourcing articles from specialized databases using specific medical subject headings terms to ensure precision and relevance. Curcumin demonstrates significant neuroprotective properties by modulating neuroinflammatory pathways, scavenging reactive oxygen species, and inhibiting the production of pro-inflammatory cytokines. Despite its potential, challenges remain regarding its limited bioavailability and the scarcity of comprehensive human clinical trials. Curcumin emerges as a promising therapeutic adjunct in AD due to its multimodal neuroprotective benefits. However, further research is required to overcome challenges related to bioavailability and to establish effective dosing regimens in human subjects. Developing novel delivery systems and formulations may enhance curcumin's therapeutic potential in AD treatment.


Assuntos
Doença de Alzheimer , Anti-Inflamatórios , Curcumina , Fármacos Neuroprotetores , Curcumina/farmacologia , Curcumina/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Humanos , Fármacos Neuroprotetores/farmacologia , Anti-Inflamatórios/farmacologia , Animais , Doenças Neuroinflamatórias/tratamento farmacológico , Antioxidantes/farmacologia , Curcuma/química , Disponibilidade Biológica
10.
Drug Dev Res ; 85(2): e22175, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38567708

RESUMO

Icaritin is a natural prenylated flavonoid derived from the Chinese herb Epimedium. The compound has shown antitumor effects in various cancers, especially hepatocellular carcinoma (HCC). Icaritin exerts its anticancer activity by modulating multiple signaling pathways, such as IL-6/JAK/STAT3, ER-α36, and NF-κB, affecting the tumor microenvironment and immune system. Several clinical trials have evaluated the safety and efficacy of icaritin in advanced HCC patients with poor prognoses, who are unsuitable for conventional therapies. The results have demonstrated that icaritin can improve survival, delay progression, and produce clinical benefits in these patients, with a favorable safety profile and minimal adverse events. Moreover, icaritin can enhance the antitumor immune response by regulating the function and phenotype of various immune cells, such as CD8+ T cells, MDSCs, neutrophils, and macrophages. These findings suggest that icaritin is a promising candidate for immunotherapy in HCC and other cancers. However, further studies are needed to elucidate the molecular mechanisms and optimal dosing regimens of icaritin and its potential synergistic effects with other agents. Therefore, this comprehensive review of the scientific literature aims to summarize advances in the knowledge of icaritin in preclinical and clinical studies as well as the pharmacokinetic, metabolism, toxicity, and mechanisms action to recognize the main challenge, gaps, and opportunities to develop a medication that cancer patients can use. Thus, our main objective was to clarify the current state of icaritin for use as an anticancer drug.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Linhagem Celular Tumoral , Microambiente Tumoral
11.
Artigo em Inglês | MEDLINE | ID: mdl-38652277

RESUMO

Arnicolide D, a potent sesquiterpene lactone from Centipeda minima, has emerged as a promising anticancer candidate, demonstrating significant efficacy in inhibiting cancer cell proliferation, inducing apoptosis, and suppressing metastasis across various cancer models. This comprehensive study delves into the molecular underpinnings of Arnicolide D's anticancer actions, emphasizing its impact on key signaling pathways such as PI3K/AKT/mTOR and STAT3, and its role in modulating cell cycle and survival mechanisms. Quantitative data from preclinical studies reveal Arnicolide D's dose-dependent cytotoxicity against cancer cell lines, including nasopharyngeal carcinoma, triple-negative breast cancer, and human colon carcinoma, showcasing its broad-spectrum anticancer potential. Given its multifaceted mechanisms and preclinical efficacy, Arnicolide D warrants further investigation in clinical settings to validate its therapeutic utility against cancer. The evidence presented underscores the need for rigorous pharmacokinetic and toxicological studies to establish safe dosing parameters for future clinical trials.

12.
Carbohydr Polym ; 336: 122121, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670753

RESUMO

This study aimed to modify chitosan (CS) by gamma irradiation and use it as a surface coating of nanoparticles (NPs) fabricated of poly lactic-co-glycolic acid (PLGA) to create mostly biocompatible nanosystems that can transport drugs to neurons. Gamma irradiation produced irradiated CS (CSγ) with a very low molecular weight (15.2-19.2 kDa). Coating NPs-PLGA with CSγ caused significant changes in their Z potential, making it slightly positive (from -21.7 ± 2.8 mV to +7.1 ± 2.3 mV) and in their particle size (184.4 0.4 ± 7.9 nm to 211.9 ± 14.04 nm). However, these changes were more pronounced in NPs coated with non-irradiated CS (Z potential = +54.0 ± 1.43 mV, size = 348.1 ± 16.44 nm). NPs coated with CSγ presented lower cytotoxicity and similar internalization levels in SH-SY5Y neuronal cells than NPs coated with non-irradiated CS, suggesting higher biocompatibility. Highly biocompatible NPs are desirable as nanocarriers to deliver drugs to the brain, as they help maintain the structure and function of the blood-brain barrier. Therefore, the NPs developed in this study could be evaluated as drug-delivery systems for treating brain diseases.


Assuntos
Quitosana , Nanopartículas , Neurônios , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Quitosana/química , Humanos , Nanopartículas/química , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Portadores de Fármacos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Tamanho da Partícula , Raios gama
13.
Prostate Int ; 12(1): 20-26, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38523897

RESUMO

Background: Metastatic hormone-sensitive prostate cancer (mHSPC) treatment has changed drastically during the last years with the emergence of androgen receptor-targeted agents (ARTAs). ARTA combined with androgen deprivation therapy has demonstrated better oncological and survival outcomes in these patients. However, the optimal choice among different ARTAs remains uncertain due to their analogous efficacy. Objectives: The objective of this study was to describe prostate-specific antigen (PSA) response and oncological outcomes of patients with mHSPC treated with apalutamide. Material and methods: Medical records from three different hospitals in Spain were used to conduct this study. Patients diagnosed with mHSPC and under apalutamide treatment were included between March 2021 and January 2023. Data regarding PSA response, overall survival (OS), and radiographic progression-free survival (rPFS) were collected and stratified by metastasis volume, timing, and stating. Results: 193 patients were included; 34.2% of patients were de novo mHSPC, and the majority was classified as m1b. The 18-month OS and rPFS were 92.5% and 88.9%, respectively. Patients with PSA levels ≤0.2 ng/ml showcased an 18-month OS rate of 98.7%, contrasting with 65.3% for those with PSA >0.2 ng/ml. Similar trends emerged for rPFS (97.4% and 53.7%, respectively). When differentiating between low-volume and high-volume metastasis, the OS rate stood at 98.4% and 80.7%, respectively, while the rPFS rates were 93% and 81.6%, respectively. No significant differences were found between groups stratified by metastasis timing. Conclusion: This real-world study on patients with mHSPC treated with apalutamide plus androgen deprivation therapy revealed robust oncological outcomes, aligning with the emerging evidence. The study's hallmark finding highlights the significance of rapid and deep PSA response as a predictor of improved oncological and survival outcomes.

14.
J Mater Sci Mater Med ; 35(1): 20, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526669

RESUMO

Xyloglucan is a rigid polysaccharide that belongs to the carbohydrate family. This hemicellulose compound has been widely used in biomedical research because of its pseudoplastic, mucoadhesive, mucomimetic, and biocompatibility properties. Xyloglucan is a polyose with no amino groups in its structure, which also limits its range of applications. It is still unknown whether grafting hydrophilic monomers onto xyloglucan can produce derivatives that overcome these shortcomings. This work aimed to prepare the first copolymers in which N-hydroxyethyl acrylamide is grafted onto tamarind xyloglucan by free-radical polymerization. The biocompatibility of these structures in vitro was evaluated using human dermal fibroblasts. Gamma radiation-induced graft polymerization was employed as an initiator by varying the radiation dose from 5-25 kGy. The structure of the graft copolymer, Xy-g-poly(N-hydroxyethyl acrylamide), was verified by thermal analysis, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy. The findings indicate that the degree of grafting and the cytotoxicity/viability of the xyloglucan-based copolymer were independent of dose. Notably, the grafted galactoxyloglucan exhibited efficient support for human dermal fibroblasts, showing heightened proliferative capacity and superior migration capabilities compared to the unmodified polymer. This copolymer might have the potential to be used in skin tissue engineering.


Assuntos
Acrilamida , Glucanos , Polímeros , Humanos , Acrilamida/química , Polimerização , Polímeros/química , Xilanos/química , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Antioxidants (Basel) ; 13(3)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38539865

RESUMO

The guanine oxidized (GO) system of Bacillus subtilis, composed of the YtkD (MutT), MutM and MutY proteins, counteracts the cytotoxic and genotoxic effects of the oxidized nucleobase 8-OxoG. Here, we report that in growing B. subtilis cells, the genetic inactivation of GO system potentiated mutagenesis (HPM), and subsequent hyperresistance, contributes to the damaging effects of hydrogen peroxide (H2O2) (HPHR). The mechanism(s) that connect the accumulation of the mutagenic lesion 8-OxoG with the ability of B. subtilis to evolve and survive the noxious effects of oxidative stress were dissected. Genetic and biochemical evidence indicated that the synthesis of KatA was exacerbated, in a PerR-independent manner, and the transcriptional coupling repair factor, Mfd, contributed to HPHR and HPM of the ΔGO strain. Moreover, these phenotypes are associated with wider pleiotropic effects, as revealed by a global proteome analysis. The inactivation of the GO system results in the upregulated production of KatA, and it reprograms the synthesis of the proteins involved in distinct types of cellular stress; this has a direct impact on (i) cysteine catabolism, (ii) the synthesis of iron-sulfur clusters, (iii) the reorganization of cell wall architecture, (iv) the activation of AhpC/AhpF-independent organic peroxide resistance, and (v) increased resistance to transcription-acting antibiotics. Therefore, to contend with the cytotoxic and genotoxic effects derived from the accumulation of 8-OxoG, B. subtilis activates the synthesis of proteins belonging to transcriptional regulons that respond to a wide, diverse range of cell stressors.

16.
Antioxidants (Basel) ; 13(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38539912

RESUMO

Pig feeding prior to the extensive fattening phase might affect the final lipid profile and product quality. This study evaluates how maternal supplementation with vitamin E (VITE) (100 mg/kg), hydroxytyrosol (HXT) (1.5 mg/kg), or combined administration (VE + HXT) affects the piglet's plasma and tissues' fatty acid profiles and lipid stability according to the sow's parity number (PN), as well as the possible changes to the lipid profile after extensive feeding. The sows' PN affected the total fatty acid profile of plasma, muscle, and liver of piglets, with lower Δ-9 and Δ-6 desaturase indices but higher Δ-5 in those from primiparous (P) than multiparous (M) sows. Dietary VITE was more effective at decreasing C16:0 and saturated fatty acids in the muscle of piglets born from M than P sows, and modified the liver phospholipids in a different way. Sows' supplementation with HXT increased C18:2n-6 in triglycerides and polyunsaturated fatty acids (PUFA) in muscle phospholipids. In the liver, HXT supplementation also increased free-PUFA and free-n-3 fatty acids. However, lipid oxidation of piglets' tissues was not affected by the antioxidant supplementation, and it was higher in the livers of piglets born from M sows. The fatty acid profile in the muscle of pigs after extensive feeding was not affected by the PN, but it was by the sows' antioxidant supplementation, with positive effects on quality by both compounds.

17.
Biol Chem ; 405(6): 395-406, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38452398

RESUMO

Checkpoint kinase 1 (Chk1) plays an important role in regulation of the cell cycle, DNA damage response and cell death, and represents an attractive target in anticancer therapy. Small-molecule inhibitors of Chk1 have been intensively investigated either as single agents or in combination with various chemotherapeutic drugs and they can enhance the chemosensitivity of numerous tumor types. Here we newly demonstrate that pharmacological inhibition of Chk1 using potent and selective inhibitor SCH900776, currently profiled in phase II clinical trials, significantly enhances cytotoxic effects of the combination of platinum-based drugs (cisplatin or LA-12) and TRAIL (tumor necrosis factor-related apoptosis inducing ligand) in human prostate cancer cells. The specific role of Chk1 in the drug combination-induced cytotoxicity was confirmed by siRNA-mediated silencing of this kinase. Using RNAi-based methods we also showed the importance of Bak-dependent mitochondrial apoptotic pathway in the combined anticancer action of SCH900776, cisplatin and TRAIL. The triple drug combination-induced cytotoxicity was partially enhanced by siRNA-mediated Mcl-1 silencing. Our findings suggest that targeting Chk1 may be used as an efficient strategy for sensitization of prostate cancer cells to killing action of platinum-based chemotherapeutic drugs and TRAIL.


Assuntos
Antineoplásicos , Quinase 1 do Ponto de Checagem , Cisplatino , Neoplasias da Próstata , Ligante Indutor de Apoptose Relacionado a TNF , Humanos , Quinase 1 do Ponto de Checagem/metabolismo , Quinase 1 do Ponto de Checagem/antagonistas & inibidores , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Compostos Organoplatínicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
18.
Int J Biol Macromol ; 262(Pt 1): 129999, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331080

RESUMO

In recent years, chitosan (CS) has received much attention as a functional biopolymer for various applications, especially in the biomedical field. It is a natural polysaccharide created by the chemical deacetylation of chitin (CT) that is nontoxic, biocompatible, and biodegradable. This natural polymer is difficult to process; however, chemical modification of the CS backbone allows improved use of functional derivatives. CS and its derivatives are used to prepare hydrogels, membranes, scaffolds, fibers, foams, and sponges, primarily for regenerative medicine. Tissue engineering (TE), currently one of the fastest-growing fields in the life sciences, primarily aims to restore or replace lost or damaged organs and tissues using supports that, combined with cells and biomolecules, generate new tissue. In this sense, the growing interest in the application of biomaterials based on CS and some of its derivatives is justifiable. This review aims to summarize the most important recent advances in developing biomaterials based on CS and its derivatives and to study their synthesis, characterization, and applications in the biomedical field, especially in the TE area.


Assuntos
Quitosana , Quitosana/uso terapêutico , Quitosana/química , Engenharia Tecidual , Materiais Biocompatíveis/uso terapêutico , Materiais Biocompatíveis/química , Medicina Regenerativa , Alicerces Teciduais
19.
PLOS Glob Public Health ; 4(1): e0002846, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38271347

RESUMO

Diabetes and depression are both serious health conditions. While their relationship is bidirectional and each condition adversely affects outcomes for the other, they are treated separately. In low and middle income countries, such as Bangladesh and Pakistan, health systems are already stretched and the integration of diabetes and depression care is rarely a priority. Within this context through interviews with patients, healthcare workers and policy makers the study explored: lived experiences of people living with depression and diabetes, current practice in mental health and diabetes care and barriers and perspectives on integrating a brief psychological therapy into diabetes care. The findings of the study included: differing patient and practitioner understandings of distress/depression, high levels of stigma for mental health and a lack of awareness and training on treating depression. While it was apparent there is a need for more holistic care and the concept of a brief psychological intervention appeared acceptable to participants, many logistical barriers to integrating a mental health intervention into diabetes care were identified. The study highlights the importance of context and of recognising drivers and understandings of distress when planning for more integrated mental and physical health services, and specifically when adapting and implementing a new intervention into existing services.

20.
J Biol Eng ; 18(1): 12, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273413

RESUMO

BACKGROUND: Polymeric nanoparticles can be used for wound closure and therapeutic compound delivery, among other biomedical applications. Although there are several nanoparticle obtention methods, it is crucial to know the adequate parameters to achieve better results. Therefore, the objective of this study was to optimize the parameters for the synthesis, purification, and freeze-drying of chitosan nanoparticles. We evaluated the conditions of agitation speed, anion addition time, solution pH, and chitosan and sodium tripolyphosphate concentration. RESULTS: Chitosan nanoparticles presented an average particle size of 172.8 ± 3.937 nm, PDI of 0.166 ± 0.008, and zeta potential of 25.00 ± 0.79 mV, at the concentration of 0.1% sodium tripolyphosphate and chitosan (pH 5.5), with a dripping time of 2 min at 500 rpm. The most representative factor during nanoparticle fabrication was the pH of the chitosan solution, generating significant changes in particle size and polydispersity index. The observed behavior is attributed to the possible excess of sodium tripolyphosphate during synthesis. We added the surfactants poloxamer 188 and polysorbate 80 to evaluate the stability improvement during purification (centrifugation or dialysis). These surfactants decreased coalescence between nanoparticles, especially during purification. The centrifugation increased the zeta potential to 40.8-56.2 mV values, while the dialyzed samples led to smaller particle sizes (152-184 nm). Finally, freeze-drying of the chitosan nanoparticles proceeded using two cryoprotectants, trehalose and sucrose. Both adequately protected the system during the process, and the sugar concentration depended on the purification process. CONCLUSIONS: In Conclusion, we must consider each surfactant's benefits in formulations for selecting the most suitable. Also, it is necessary to do more studies with the molecule to load. At the same time, the use of sucrose and trehalose generates adequate protection against the freeze-drying process, even at a 5% w/v concentration. However, adjusting the percentage concentration by weight must be made to work with the CS-TPP NPs purified by dialysis.

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