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1.
Chemistry ; 30(33): e202400933, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609334

RESUMO

A relaxin-like gonad-stimulating peptide (RGP), Aso-RGP, featuring six cysteine residues, was identified in the Crown-of-Thorns Starfish (COTS, Acanthaster cf. solaris) and initially produced through recombinant yeast expression. This method yielded a single-chain peptide with an uncleaved C-peptide (His Tag) and suboptimal purity. Our objective was to chemically synthesize Aso-RGP in its mature form, comprising two chains (A and B) and three disulfide bridges, omitting the C-peptide. Furthermore, we aimed to synthesize a newly identified relaxin-like peptide, Aso-RLP2, from COTS, which had not been previously synthesized. This paper reports the first total chemical synthesis of Aso-RGP and Aso-RLP2. Aso-RGP synthesis proceeded without major issues, whereas the A-chain of Aso-RLP2, in its reduced and unfolded state with two free thiols, presented considerable challenges. These were initially marked by "messy" RP-HPLC profiles, typically indicative of synthesis failure. Surprisingly, oxidizing the A-chain significantly improved the RP-HPLC profile, revealing the main issue was not synthesis failure but the peptide's aggregation tendency, which initially obscured analysis. This discovery highlights the critical need to account for aggregation in peptide synthesis and analysis. Ultimately, our efforts led to the successful synthesis of both peptides with purities exceeding 95 %.


Assuntos
Dissulfetos , Peptídeos , Estrelas-do-Mar , Estrelas-do-Mar/química , Dissulfetos/química , Peptídeos/química , Peptídeos/síntese química , Animais , Cromatografia Líquida de Alta Pressão , Sequência de Aminoácidos , Cisteína/química , Oxirredução
2.
Med Microbiol Immunol ; 213(1): 14, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38977511

RESUMO

Mycobacterium tuberculosis, a lethal pathogen in human history, causes millions of deaths annually, which demands the development of new concepts of drugs. Considering this fact, earlier research has explored the anti-tuberculosis potential of a probiotic strain, Lactocaseibacillus rhamnosus PMC203, leading to a subsequent focus on the molecular mechanism involved in its effect, particularly on autophagy. In this current study, immunoblotting-based assay exhibited a remarkable expression of autophagy marker LC3-II in the PMC203 treated group compared to an untreated group. A remarkable degradation of p62 was also noticed within treated cells compared to control. Furthermore, the immunofluorescence-based assay showed significant fold change in fluorescence intensity for alexa-647-LC3 and alexa-488-LC3, whereas p62 was degraded noticeably. Moreover, lysosomal biogenesis generation was elevated significantly in terms of LAMP1 and acidic vesicular organelles. As a result, PMC203-induced autophagy played a vital role in reducing M. tuberculosis burden within the macrophages in treated groups compared to untreated group. A colony -forming unit assay also revealed a significant reduction in M. tuberculosis in the treated cells over time. Additionally, the candidate strain significantly upregulated the expression of autophagy induction and lysosomal biogenesis genes. Together, these results could enrich our current knowledge of probiotics-mediated autophagy in tuberculosis and suggest its implications for innovatively managing tuberculosis.


Assuntos
Autofagia , Lacticaseibacillus rhamnosus , Macrófagos , Mycobacterium tuberculosis , Probióticos , Mycobacterium tuberculosis/genética , Lacticaseibacillus rhamnosus/fisiologia , Lacticaseibacillus rhamnosus/metabolismo , Macrófagos/microbiologia , Humanos , Lisossomos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Carga Bacteriana , Tuberculose/microbiologia
3.
Reprod Health ; 20(Suppl 1): 191, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760864

RESUMO

BACKGROUND: In 2019, the World Health Organization identified improving access to safe abortion as an important priority toward improving sexual and reproductive health and rights and achieving Sustainable Development Goals. One strategy for addressing this priority is strengthening access to medicines for medical abortion. All 11 countries in the South-East Asia Region have some indications for legal abortion and permit post-abortion care. Therefore, strengthening access to medical abortion medicines is a reasonable strategy for improving access to safe abortion for the Region. METHODOLOGY: We applied an adapted version of an existing World Health Organization landscape assessment protocol for the availability of medical abortion medicines at the country-level in the South-East Asia Region. We collected publicly available data on the existence of national health laws, policies, and standard treatment guidelines; inclusion of medical abortion medicines in the national essential medicines list; and marketing authorization status for medical abortion medicines for each country and verified by Ministries of health. The findings were once more presented, discussed and recommendations were formulated during regional technical consultation workshop. Each country teams participated in the process, and subsequently, the suggestions were validated by representatives from Ministries of Health.. RESULTS: Few countries in the Region currently have national policies and guidelines for comprehensive safe abortion. However, either mifepristone-misoprostol in combination or misoprostol alone (for other indications) is included in national essential medicines lists in all countries except Indonesia and Sri Lanka. Few countries earmark specific public funds for procuring and distributing medical abortion commodities. In countries where abortion is legal, the private sector and NGOs support access to medical abortion information and medicines. Several countries only allow registered medical practitioners or specialists to administer medical abortion. CONCLUSION: Following this rapid participatory assessment and technical consultation workshop, the World Health Organization South-East Asia Regional Technical Advisory and Sexual and Reproductive Health and Rights technical committee recommended priority actions for policy and advocacy, service delivery, and monitoring and evaluation, and indicated areas for support.


Assuntos
Aborto Induzido , Acessibilidade aos Serviços de Saúde , Organização Mundial da Saúde , Humanos , Sudeste Asiático , Feminino , Gravidez , Aborto Induzido/métodos , Abortivos , Medicamentos Essenciais/provisão & distribuição
4.
J Am Chem Soc ; 145(37): 20242-20247, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37439676

RESUMO

Peptides and peptidomimetics are attractive drug candidates because of their high target specificity and low-toxicity profiles. Developing peptidomimetics using hydrocarbon (HC)-stapling or other stapling strategies has gained momentum because of their high stability and resistance to proteases; however, they have limitations. Here, we take advantage of the α-methyl group and an aromatic phenyl ring in a unique unnatural amino acid, α-methyl-l-phenylalanine (αF), and propose a novel, noncovalent stapling strategy to stabilize peptides. We utilized this strategy to create an α-helical B-chain mimetic of a complex insulin-like peptide, human relaxin-3 (H3 relaxin). Our comprehensive data set (in vitro, ex vivo, and in vivo) confirmed that the new high-yielding B-chain mimetic, H3B10-27(13/17αF), is remarkably stable in serum and fully mimics the biological function of H3 relaxin. H3B10-27(13/17αF) is an excellent scaffold for further development as a drug lead and an important tool to decipher the physiological functions of the neuropeptide G protein-coupled receptor, RXFP3.


Assuntos
Peptidomiméticos , Relaxina , Humanos , Relaxina/química , Relaxina/metabolismo , Receptores Acoplados a Proteínas G/química , Conformação Proteica em alfa-Hélice , Fenilalanina
5.
Bioconjug Chem ; 34(6): 1014-1018, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37192432

RESUMO

Exenatide was the first marketed GLP-1 receptor agonist for the treatment of type 2 diabetes. Modification to the chemical structure or the formulation has the potential to increase the stability of exenatide. We introduced human complex-type sialyloligosaccharide to exenatide at the native Asn28 position. The synthesis was achieved using both solid phase peptide synthesis (SPPS) and Omniligase-1-mediated chemoenzymatic ligation. The results demonstrate that glycosylation increases the proteolytic stability of exenatide while retaining its full biological activity.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Exenatida , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes , Glicosilação , Peptídeo Hidrolases , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Peçonhas
6.
Chem Rev ; 121(8): 4531-4560, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33689304

RESUMO

The pancreatic peptide hormone insulin, first discovered exactly 100 years ago, is essential for glycemic control and is used as a therapeutic for the treatment of type 1 and, increasingly, type 2 diabetes. With a worsening global diabetes epidemic and its significant health budget imposition, there is a great demand for new analogues possessing improved physical and functional properties. However, the chemical synthesis of insulin's intricate 51-amino acid, two-chain, three-disulfide bond structure, together with the poor physicochemical properties of both the individual chains and the hormone itself, has long represented a major challenge to organic chemists. This review provides a timely overview of the past efforts to chemically assemble this fascinating hormone using an array of strategies to enable both correct folding of the two chains and selective formation of disulfide bonds. These methods not only have contributed to general peptide synthesis chemistry and enabled access to the greatly growing numbers of insulin-like and cystine-rich peptides but also, today, enable the production of insulin at the synthetic efficiency levels of recombinant DNA expression methods. They have led to the production of a myriad of novel analogues with optimized structural and functional features and of the feasibility for their industrial manufacture.


Assuntos
Técnicas de Química Sintética/métodos , Insulina/síntese química , Sequência de Aminoácidos , Animais , Humanos , Insulina/análogos & derivados , Insulina/química , Conformação Proteica
7.
Int J Mol Sci ; 24(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37628851

RESUMO

Human relaxin-2 (H2 relaxin) is a peptide hormone with potent vasodilatory and anti-fibrotic effects, which is of interest for the treatment of heart failure and fibrosis. H2 relaxin binds to the Relaxin Family Peptide Receptor 1 (RXFP1). Native H2 relaxin is a two-chain, three-disulfide-bond-containing peptide, which is unstable in human serum and difficult to synthesize efficiently. In 2016, our group developed B7-33, a single-chain peptide derived from the B-chain of H2 relaxin. B7-33 demonstrated poor affinity and potency in HEK cells overexpressing RXFP1; however, it displayed equivalent potency to H2 relaxin in fibroblasts natively expressing RXFP1, where it also demonstrated the anti-fibrotic effects of the native hormone. B7-33 reversed organ fibrosis in numerous pre-clinical animal studies. Here, we detail our efforts towards a minimal H2 relaxin scaffold and attempts to improve scaffold activity through Aib substitution and hydrocarbon stapling to re-create the peptide helicity present in the native H2 relaxin.


Assuntos
Insuficiência Cardíaca , Hormônios Peptídicos , Relaxina , Animais , Humanos , Relaxina/farmacologia , Fibroblastos , Insuficiência Cardíaca/tratamento farmacológico , Domínios Proteicos
8.
Int J Mol Sci ; 24(7)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37047588

RESUMO

Human relaxin-2 (H2 relaxin) is therapeutically very important due to its strong anti-fibrotic, vasodilatory, and cardioprotective effects. Therefore, relaxin's receptor, relaxin family peptide receptor 1 (RXFP1), is a potential target for the treatment of fibrosis and related disorders, including heart failure. H2 relaxin has a complex two-chain structure (A and B) and three disulfide bridges. Our laboratory has recently developed B7-33 peptide, a single-chain agonist based on the B-chain of H2 relaxin. However, the peptide B7-33 has a short circulation time in vitro in serum (t1/2 = ~6 min). In this study, we report structure-activity relationship studies on B7-33 utilizing different fatty-acid conjugations at different positions. We have shown that by fatty-acid conjugation with an appropriate spacer length, the in vitro half-life of B7-33 can be increased from 6 min to 60 min. In the future, the lead lipidated molecule will be studied in animal models to measure its PK/PD properties, which will lead to their pre-clinical applications.


Assuntos
Relaxina , Animais , Humanos , Relaxina/farmacologia , Receptores Acoplados a Proteínas G/química , Relação Estrutura-Atividade , Fibrose
9.
Small ; 18(8): e2104387, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34716658

RESUMO

Metal-organic frameworks (MOFs) have potential applications in removing pollutants such as heavy metals, oils, and toxins from water. However, due to the intrinsic fragility of MOFs and their fine powder form, there are still technical barriers to their practical application such as blockage of pipes, difficulty in recovery, and potential environmental toxicity. Therefore, attention has focused on approaches to convert nanocrystalline MOFs into macroscopic materials to overcome these limitations. Recently, strategies for shaping MOFs into beads (0D), nanofibers (1D), membranes (2D), and gels/sponges (3D) with macrostructures are developed including direct mixing, in situ growth, or deposition of MOFs with polymers, cotton, foams or other porous substrates. In this review, successful strategies for the fabrication of macroscopic materials from MOFs and their applications in removing pollutants from water including adsorption, separation, and advanced oxidation processes, are discussed. The relationship between the macroscopic performance and the microstructure of materials, and how the range of 0D to 3D macroscopic materials can be used for water treatment are also outlined.


Assuntos
Poluentes Ambientais , Estruturas Metalorgânicas , Metais Pesados , Purificação da Água , Adsorção , Estruturas Metalorgânicas/química , Metais Pesados/química
10.
Cell Tissue Res ; 389(1): 1-9, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35596811

RESUMO

The gastrointestinal hormone, insulin-like peptide 5 (INSL5), is found in large intestinal enteroendocrine cells (EEC). One of its functions is to stimulate nerve circuits that increase propulsive activity of the colon through its receptor, the relaxin family peptide 4 receptor (RXFP4). To investigate the mechanisms that link INSL5 to stimulation of propulsion, we have determined the localisation of cells expressing Rxfp4 in the mouse colon, using a reporter mouse to locate cells expressing the gene. The fluorescent signal indicating the location of Rxfp4 expression was in EEC, the greatest overlap of Rxfp4-dependent labelling being with cells containing 5-HT. In fact, > 90% of 5-HT cells were positive for Rxfp4 labelling. A small proportion of cells with Rxfp4-dependent labelling was 5-HT-negative, 11-15% in the distal colon and rectum, and 35% in the proximal colon. Of these, some were identified as L-cells by immunoreactivity for oxyntomodulin. Rxfp4-dependent fluorescence was also found in a sparse population of nerve endings, where it was colocalised with CGRP. We used the RXFP4 agonist, INSL5-A13, to activate the receptor and probe the role of the 5-HT cells in which it is expressed. INSL5-A13 administered by i.p. injection to conscious mice caused an increase in colorectal propulsion that was antagonised by the 5-HT3 receptor blocker, alosetron, also given i.p. We conclude that stimuli that excite INSL5-containing colonic L-cells release INSL5 that, through RXFP4, excites 5-HT release from neighbouring endocrine cells, which in turn acts on 5-HT3 receptors of enteric sensory neurons to elicit propulsive reflexes.


Assuntos
Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Relaxina , Animais , Células Enterocromafins/metabolismo , Células Enteroendócrinas/metabolismo , Intestino Grosso , Camundongos , Serotonina
11.
FASEB J ; 35(5): e21595, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33908676

RESUMO

Current histological measurement techniques for interstitial collagen, the basis of interstitial fibrosis, are semi-quantitative at best and only provide a ratio of collagen levels within tissues. The Genesis200 imaging system and supplemental image analysis software, FibroIndex from HistoIndex, is a novel, automated platform that uses second-harmonic generation (SHG) for imaging and characterization of interstitial collagen deposition and additional characteristics, in the absence of any staining. However, its ability to quantify renal fibrosis requires investigation. This study compared SHG imaging of renal fibrosis in mice with unilateral ureteric obstruction (UUO), to that of Masson's trichrome staining (MTS) and immunohistochemistry (IHC) of collagen I. Additionally, the platform generated data on collagen morphology and distribution patterns. While all three methods determined that UUO-injured mice underwent significantly increased renal fibrosis after 7 days, the HistoIndex platform additionally determined that UUO-injured mice had a significantly increased collagen-to-tissue cross reticulation ratio (all P < .001 vs sham group). Furthermore, in UUO-injured mice treated with the relaxin family peptide receptor-1 agonists, relaxin (0.5 mg/kg/day) or B7-33 (0.25 mg/kg/day), or angiotensin converting enzyme-inhibitor, perindopril (1 mg/kg/day) over the 7-day period, only the HistoIndex platform determined that the drug-induced prevention of renal fibrosis correlated with significantly reduced collagen fiber thickness and collagen-to-tissue cross reticulation ratio, but increased collagen fiber counts. Relaxin or B7-33 treatment also increased renal matrix metalloproteinase-2 and reduced tissue inhibitor of metalloproteinase-1 levels (all P < .01 vs UUO alone). This study demonstrated the diagnostic value of the HistoIndex platform over currently used staining techniques.


Assuntos
Fibrose/patologia , Nefropatias/patologia , Fragmentos de Peptídeos/farmacologia , Relaxina/farmacologia , Obstrução Ureteral/complicações , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Fibrose/tratamento farmacológico , Fibrose/etiologia , Nefropatias/tratamento farmacológico , Nefropatias/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
12.
Mol Biol Rep ; 49(11): 10875-10883, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35931874

RESUMO

The process of cell division plays a vital role in cancer progression. Cell proliferation and error-free chromosomes segregation during mitosis are central events in life cycle. Mistakes during cell division generate changes in chromosome content and alter the balances of chromosomes number. Any defects in expression of TIF1 family proteins, SAC proteins network, mitotic checkpoint proteins involved in chromosome mis-segregation and cancer development. Here we discuss the function of organelles deal with the chromosome segregation machinery, proteins and correction mechanisms involved in the accurate chromosome segregation during mitosis.


Assuntos
Segregação de Cromossomos , Neoplasias , Humanos , Mitose/genética , Ciclo Celular/genética , Pontos de Checagem da Fase M do Ciclo Celular , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Neoplasias/genética , Neoplasias/terapia , Cinetocoros/metabolismo
13.
BMC Public Health ; 22(1): 181, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35081905

RESUMO

BACKGROUND: Hypertension is a known risk factor for several chronic conditions including diabetes and cardiovascular diseases. However, little is known about its impact on Health-related quality of life (HRQoL) in the context of Bangladesh. This study aimed to evaluate the association of hypertension on HRQoL among Bangladeshi patients corresponding to the socio-demographic condition, comorbid conditions, treatment, and health outcomes. METHODS: A hospital based cross-sectional study was conducted using a pre-tested structured questionnaire among patients with hypertension in 22 tertiary medical college hospitals in Bangladesh. The study recruited male and female hypertensive patients of age ≥18 years between July 2020 to February 2021 using consecutive sampling methods. Health related quality of life was measured using the widely-used index of EQ-5D that considers 243 different health-related attributes and uses a scale in which 0 indicates a health state equivalent to death and 1 indicates perfect health status. The five dimensions of the quality index included mobility, self-care, usual activities, pain or discomfort, and anxiety or depression. Ordered logit regression and linear regression models were used to estimate the predictors of comorbidity and HRQoL. RESULTS: Of the 1,912 hypertensive patients, 56.2% were female, 86.5% were married, 70.7% were either overweight or obese, 67.6% had a family history of hypertension, and 85.5% were on anti-hypertensive medication. Among the individuals with comorbidities, 47.6% had diabetes, 32.3% were obese, 16.2% had heart disease, 15% were visually impaired, and 13.8% were suffering from psychological diseases. HRQoL was found to be inversely proportional to the number of comorbidities. The most frequent comorbidities of diabetes and obesity showed the highest EQ- 5D mean utilities of 0.59 and 0.64, respectively. CONCLUSIONS: Prevalent comorbidities, diabetes and obesity were found to be the significant underlying causes of declining HRQoL. It is recommended that the comorbidities should be adequately addressed for better HRQoL. Special attention should be given to address mental health issues of patients with hypertension.


Assuntos
Hipertensão , Qualidade de Vida , Adolescente , Bangladesh/epidemiologia , Comorbidade , Estudos Transversais , Feminino , Hospitais , Humanos , Hipertensão/epidemiologia , Hipertensão/psicologia , Masculino , Obesidade/epidemiologia , Qualidade de Vida/psicologia , Inquéritos e Questionários
14.
Int J Mol Sci ; 23(13)2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35806076

RESUMO

Chronic NLRP3 inflammasome activation can promote fibrosis through its production of interleukin (IL)-1ß and IL-18. Conversely, recombinant human relaxin (RLX) can inhibit the pro-fibrotic interactions between IL-1ß, IL-18 and transforming growth factor (TGF)-ß1. Here, the broader extent by which RLX targeted the myofibroblast NLRP3 inflammasome to mediate its anti-fibrotic effects was elucidated. Primary human cardiac fibroblasts (HCFs), stimulated with TGF-ß1 (to promote myofibroblast (HCMF) differentiation), LPS (to prime the NLRP3 inflammasome) and ATP (to activate the NLRP3 inflammasome) (T+L+A) or benzoylbenzoyl-ATP (to activate the ATP receptor; P2X7R) (T+L+Bz), co-expressed relaxin family peptide receptor-1 (RXFP1), the angiotensin II type 2 receptor (AT2R) and P2X7R, and underwent increased protein expression of toll-like receptor (TLR)-4, NLRP3, caspase-1, IL-1ß and IL-18. Whilst RLX co-administration to HCMFs significantly prevented the T+L+A- or T+L+Bz-stimulated increase in these end points, the inhibitory effects of RLX were annulled by the pharmacological antagonism of either RXFP1, AT2R, P2X7R, TLR-4, reactive oxygen species (ROS) or caspase-1. The RLX-induced amelioration of left ventricular inflammation, cardiomyocyte hypertrophy and fibrosis in isoproterenol (ISO)-injured mice, was also attenuated by P2X7R antagonism. Thus, the ability of RLX to ameliorate the myofibroblast NLRP3 inflammasome as part of its anti-fibrotic effects, appeared to involve RXFP1, AT2R, P2X7R and the inhibition of TLR-4, ROS and caspase-1.


Assuntos
Inflamassomos , Relaxina , Trifosfato de Adenosina/metabolismo , Angiotensina II/metabolismo , Animais , Caspase 1/metabolismo , Fibrose , Inflamassomos/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Camundongos , Miofibroblastos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Relaxina/metabolismo , Relaxina/farmacologia , Receptor 4 Toll-Like/metabolismo
15.
Saudi Pharm J ; 30(10): 1454-1463, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36387333

RESUMO

Objective: Resveratrol is a polyphenolic compound that possesses strong antioxidant and anti-inflammatory activities. This study evaluated the effects of resveratrol on oxidative stress, fibrosis and multiple genes regulation in the kidneys of high fat (HF) diet-fed rats. Methods: Wistar rats were fed with HF diet for eight weeks. These rats were also treated with resveratrol for eight weeks. Finally, kidney tissue samples were isolated from all sacrificed rats. The histological changes, creatinine and uric acid levels, oxidative stress parameters such as malondialdehyde (MDA), nitric oxide, and advanced oxidation protein product (AOPP) levels were analyzed. The antioxidant enzymes such as catalase, superoxide dismutase (SOD) activities and reduced glutathione (GSH) levels; gene expression of inflammatory and fibrosis-related genes namely, inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), transforming growth factor beta1 (TGF-ß1), and collagen-1 were assessed. Moreover, gene expression of oxidative stress-related genes such as nuclear factor erythroid 2-related factor 2 (Nrf-2), SOD, catalase, and glutathione reductase, were also assessed. Results: HF diet-fed rats showed increased creatinine and uric acid levels in plasma which were lowered by resveratrol treatment. The study findings also revealed that resveratrol counterbalanced the oxidative stress and prevented the expression of the inflammatory genes; restored the catalase and SOD activities followed by the up-regulation of antioxidant genes expression in the kidneys of HF diet-fed rats. HF diet caused the Nrf-2 down-regulation followed by the decreased expression of HO-1 and HO-2 genes, which was restored by resveratrol treatment. Moreover, the histological assessment showed lipotoxicity and increased fibrosis in the kidneys of HF diet-fed rats. Resveratrol prevented the kidney fibrosis probably by limiting oxidative stress, inflammation, and down-regulating TGF-ß1 mediated signaling pathway. Conclusion: In conclusion, resveratrol treatment showed beneficial effects in preventing oxidative stress and fibrosis in the kidneys of HF diet-fed rats probably by modulating the gene expression of oxidative stress and inflammation related factors and enzymes.

16.
Bioconjug Chem ; 32(10): 2148-2153, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34494823

RESUMO

The current commercially available glucagon formulations for the treatment of severe hypoglycemia must be reconstituted immediately prior to use, owing to the susceptibility of glucagon to fibrillation and aggregation in an aqueous solution. This results in the inconvenience of handling, misuse, and wastage of this drug. To address these issues, we synthesized a glycosylated glucagon analogue in which the 25th residue (Trp) was replaced with a cysteine (Cys) and a Br-disialyloligosaccharide was conjugated at the Cys thiol moiety. The resulting analogue, glycoglucagon, is a highly potent full agonist at the glucagon receptor. Importantly, glycoglucagon exhibits markedly reduced propensity for fibrillation and enhanced thermal and metabolic stability. This novel analogue is thus a valuable lead for producing stable liquid glucagon formulations that will improve patient compliance and minimize wastage.


Assuntos
Glucagon , Hipoglicemia , Cisteína , Humanos
17.
FASEB J ; 34(6): 8217-8233, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32297670

RESUMO

Fibrosis is a hallmark of several cardiovascular diseases. The relaxin family peptide receptor 1 (RXFP1) agonist, relaxin, has rapidly occurring anti-fibrotic actions which are mediated through RXFP1 and angiotensin II receptor crosstalk on renal and cardiac myofibroblasts. Here, we investigated whether this would allow relaxin to indirectly activate angiotensin II type 2 receptor (AT2 R)-specific signal transduction in primary human cardiac myofibroblasts (HCMFs). The anti-fibrotic effects of recombinant human relaxin (RLX; 16.8 nM) or the AT2 R-agonist, Compound 21 (C21; 1 µM), were evaluated in TGF-ß1-stimulated HCMFs, in the absence or presence of an RXFP1 antagonist (1 µM) or AT2 R antagonist (0.1 µM) to confirm RXFP1-AT2 R crosstalk. Competition binding for RXFP1 was determined. Western blotting was performed to determine which AT2 R-specific protein phosphatases were expressed by HCMFs; then, the anti-fibrotic effects of RLX and/or C21 were evaluated in the absence or presence of pharmacological inhibition (NSC95397 (1 µM) for MKP-1; okadaic acid (10 nM) for PP2A) or siRNA-knockdown of these phosphatases after 72 hours. The RLX- or C21-induced increase in ERK1/2 and nNOS phosphorylation, and decrease in α-SMA (myofibroblast differentiation) and collagen-I expression by HCMFs was abrogated by pharmacological blockade of RXFP1 or the AT2 R, confirming RXFP1-AT2 R crosstalk in these cells. HCMFs were found to express AT2 R-dependent MKP-1 and PP2A phosphatases, while pharmacological blockade or siRNA-knockdown of either phosphatase also abolished RLX and/or C21 signal transduction in HCMFs (all P < .05 vs RLX or C21 alone). These findings demonstrated that RLX can indirectly activate AT2 R-dependent phosphatase activity in HCMFs by signaling through RXFP1-AT2 R crosstalk, which have important therapeutic implications for its anti-fibrotic actions.


Assuntos
Fibrose/tratamento farmacológico , Fibrose/metabolismo , Coração/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Receptor Tipo 2 de Angiotensina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Relaxina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana , Humanos , Óxido Nítrico Sintase Tipo I/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo
18.
J Am Chem Soc ; 142(3): 1164-1169, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31850747

RESUMO

Glycosylation is an accepted strategy to improve the therapeutic value of peptide and protein drugs. Insulin and its analogues are life-saving drugs for all type I and 30% of type II diabetic patients. However, they can readily form fibrils which is a significant problem especially for their use in insulin pumps. Because of the solubilizing and hydration effects of sugars, it was thought that glycosylation of insulin could inhibit fibril formation and lead to a more stable formulation. Since enzymatic glycosylation results in heterogeneous products, we developed a novel chemical strategy to produce a homogeneous glycoinsulin (disialo-glycoinsulin) in excellent yield (∼60%). It showed a near-native binding affinity for insulin receptors A and B in vitro and high glucose-lowering effects in vivo, irrespective of the route of administration (s.c. vs i.p.). The glycoinsulin retained insulin-like helical structure and exhibited improved stability in human serum. Importantly, our disialo-glycoinsulin analogue does not form fibrils at both high concentration and temperature. Therefore, it is an excellent candidate for clinical use in insulin pumps.


Assuntos
Glucose/química , Insulina/síntese química , Glicosilação , Humanos , Insulina/química , Microscopia de Força Atômica
19.
Biochem Biophys Res Commun ; 533(3): 559-564, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-32980116

RESUMO

Human ghrelin receptor (GHSR) is a recognized prospective target in the diagnosis and therapy of multiple cancer types. To gain a better understanding of this receptor signaling system, we have synthesized a novel full-length ghrelin analog that is fluorescently labeled at the side-chain of a C-terminal cysteine extension. This analog exhibited nanomolar affinity and potency for the ghrelin receptor. It shows comparable efficacy with that of endogenous ghrelin. The fluorescently-labeled ghrelin analog is a valuable tool for in vitro imaging of cell lines that express ghrelin receptor.


Assuntos
Grelina/análogos & derivados , Grelina/síntese química , Proteínas Luminescentes/síntese química , Proteínas Luminescentes/metabolismo , Fluorescência , Células HEK293 , Humanos , Proteínas Luminescentes/química , Receptores de Grelina/metabolismo
20.
Pharmacol Res ; 152: 104602, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31846761

RESUMO

Diabesity is the combination of type 2 diabetes and obesity characterized by chronic low-grade inflammation. The Wnt signaling act as an evolutionary pathway playing crucial role in regulating cellular homeostasis and energy balance from hypothalamus to metabolic organs. Aberrant activity of certain appendages in the canonical and non-canonical Wnt system deregulates metabolism and leads to adipose tissue expansion, this key event initiates metabolic stress causing metaflammation and obesity. Metaflammation induced obesity initiates abnormal development of adipocytes mediating through the non-canonical Wnt signaling inhibition of canonical Wnt pathway to fan the flames of adipogenesis. Moreover, activation of toll like receptor (TLR)-4 signaling in metabolic stress invites immune cells to release pro-inflammatory cytokines for recruitment of macrophages in adipose tissues, further causes polarization of macrophages into M1(classically activated) and M2 (alternatively activated) subtypes. These events end with chronic low-grade inflammation which interferes with insulin signaling in metabolic tissues to develop type 2 diabetes. However, there is a dearth in understanding the exact mechanism of Wnt-TLR axis during diabesity. This review dissects the molecular facets of Wnt and TLRs that modulates cellular components during diabesity and provides current progress, challenges and alternative therapeutic strategies at preclinical and clinical level.


Assuntos
Adipogenia , Diabetes Mellitus Tipo 2/metabolismo , Obesidade/metabolismo , Receptores Toll-Like/metabolismo , Proteínas Wnt/metabolismo , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Inflamação/metabolismo , Obesidade/tratamento farmacológico , Transdução de Sinais
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