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1.
Mol Cell Biochem ; 479(2): 233-242, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37027096

RESUMO

Abdominal aortic aneurysms (AAA) result from maladaptive remodeling of the vascular wall and reduces structural integrity. Angiotensin II (AngII) infusion has become a standard laboratory model for studying AAA initiation and progression. We determined the different vasoactive responses of various mouse arteries to Ang II. Ex vivo isometric tension analysis was conducted on 18-week-old male C57BL/6 mice (n = 4) brachiocephalic arteries (BC), iliac arteries (IL), and abdominal (AA) and thoracic aorta (TA). Arterial rings were mounted between organ hooks, gently stretched and an AngII dose response was performed. Rings were placed in 4% paraformaldehyde for immunohistochemistry analysis to quantify peptide expression of angiotensin type 1 (AT1R) and 2 receptors (AT2R) in the endothelium, media, and adventitia. Results from this study demonstrated vasoconstriction responses in IL were significantly higher at all AngII doses when compared to BC, and TA and AA responses (maximum constriction-IL: 68.64 ± 5.47% vs. BC: 1.96 ± 1.00%; TA: 3.13 ± 0.16% and AA: 2.75 ± 1.77%, p < 0.0001). Expression of AT1R was highest in the endothelium of IL (p < 0.05) and in the media and (p < 0.05) adventitia (p < 0.05) of AA. In contrast, AT2R expression was highest in endothelium (p < 0.05), media (p < 0.01, p < 0.05) and adventitia of TA. These results suggest that mouse arteries display different vasoactive responses to AngII, and the exaggerated response in IL arteries may play a role during AAA development.


Assuntos
Aneurisma da Aorta Abdominal , Aneurisma Aórtico , Hormônios Peptídicos , Masculino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Artéria Ilíaca , Angiotensina II/farmacologia , Artérias , Aneurisma da Aorta Abdominal/induzido quimicamente , Angiotensina I
2.
Int J Mol Sci ; 24(24)2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38139391

RESUMO

Quantum pharmacology introduces theoretical models to describe the possibility of ultra-high dilutions to produce biological effects, which may help to explain the placebo effect observed in hypertensive clinical trials. To determine this within physiology and to evaluate novel ARBs, we tested the ability of known angiotensin II receptor blockers (ARBs) (candesartan and telmisartan) used to treat hypertension and other cardiovascular diseases, as well as novel ARBs (benzimidazole-N-biphenyl tetrazole (ACC519T), benzimidazole-bis-N,N'-biphenyl tetrazole (ACC519T(2)) and 4-butyl-N,N0-bis[[20-2Htetrazol-5-yl)biphenyl-4-yl]methyl)imidazolium bromide (BV6(K+)2), and nirmatrelvir (the active ingredient in Paxlovid) to modulate vascular contraction in iliac rings from healthy male New Zealand White rabbits in responses to various vasopressors (angiotensin A, angiotensin II and phenylephrine). Additionally, the hemodynamic effect of ACC519T and telmisartan on mean arterial pressure in conscious rabbits was determined, while the ex vivo ability of BV6(K+)2 to activate angiotensin-converting enzyme-2 (ACE2) was also investigated. We show that commercially available and novel ARBs can modulate contraction responses at ultra-high dilutions to different vasopressors. ACC519T produced a dose-dependent reduction in rabbit mean arterial pressure while BV6(K+)2 significantly increased ACE2 metabolism. The ability of ARBs to inhibit contraction responses even at ultra-low concentrations provides evidence of the existence of quantum pharmacology. Furthermore, the ability of ACC519T and BV6(K+)2 to modulate blood pressure and ACE2 activity, respectively, indicates their therapeutic potential against hypertension.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II , Hipertensão , Coelhos , Masculino , Animais , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Telmisartan/farmacologia , Enzima de Conversão de Angiotensina 2/farmacologia , Antagonistas de Receptores de Angiotensina/farmacologia , Artéria Ilíaca , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Benzimidazóis/uso terapêutico , Tetrazóis/farmacologia , Tetrazóis/uso terapêutico , Hipertensão/tratamento farmacológico , Pressão Sanguínea
3.
Nutrients ; 15(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37513606

RESUMO

Hyperhomocysteinemia (HHcy) worsens cardiovascular outcomes by impairing vascular function and promoting chronic inflammation via release of danger-associated molecular patterns, such as high-mobility group box-1 (HMGB-1). Elevated levels of HMGB-1 have recently been reported in patients with HHcy. Therefore, targeting HMGB-1 may be a potential therapy to improve HHcy-induced cardiovascular pathologies. This study aimed to further elucidate HMGB-1's role during acute HHcy and HHcy-induced atherogenesis and to determine if inhibiting HMGB-1 with glycyrrhizic acid (Glyz) improved vascular function. Male New Zealand White rabbits (n = 25) were placed on either a standard control chow (CD; n = 15) or atherogenic diet (AD; n = 10) for 4 weeks. Rabbit serum and Krebs taken from organ bath studies were collected to quantify HMGB-1 levels. Isometric tension analysis was performed on abdominal aorta (AA) rings from CD and AD rabbits. Rings were incubated with homocysteine (Hcy) [3 mM] for 60 min to induce acute HHcy or rhHMGB-1 [100 nM]. Vascular function was assessed by relaxation to cumulative doses of acetylcholine. Markers of vascular dysfunction and inflammation were quantified in the endothelium, media, and adventitia of AA rings. HMGB-1 was significantly upregulated in serum (p < 0.0001) and Krebs (p < 0.0001) after Hcy exposure or an AD. Incubation with Hcy (p < 0.0001) or rhHMGB-1 (p < 0.0001) and an AD (p < 0.0001) significantly reduced relaxation to acetylcholine, which was markedly improved by Glyz. HMGB-1 expression was elevated (p < 0.0001) after Hcy exposure and AD (p < 0.0001) and was normalized after Glyz treatment. Moreover, markers of vascular function, cell stress and inflammation were also reduced after Glyz. These results demonstrate that HMGB-1 has a central role during HHcy-induced vascular dysfunction and inhibiting it with Glyz could be a potential treatment option for cardiovascular diseases.


Assuntos
Aterosclerose , Hiper-Homocisteinemia , Masculino , Coelhos , Animais , Acetilcolina/farmacologia , Ácido Glicirrízico/farmacologia , Inflamação/metabolismo , Proteínas HMGB , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/tratamento farmacológico , Homocisteína
4.
Nutrients ; 15(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37299525

RESUMO

The shift in modern dietary regimens to "Western style" and sedentary lifestyles are believed to be partly responsible for the increase in the global burden of cardiovascular diseases. Natural products have been used throughout human history as treatments for a plethora of pathological conditions. Taurine and, more recently, black pepper have gained attention for their beneficial health effects while remaining non-toxic even when ingested in excess. Taurine, black pepper, and the major terpene constituents found in black pepper (i.e., ß-caryophyllene; α-pinene; ß-pinene; α-humulene; limonene; and sabinene) that are present in PhytoCann BP® have been shown to have cardioprotective effects based on anti-inflammatory, antioxidative, anti-hypertensive and anti-atherosclerotic mechanisms. This comprehensive review of the literature focuses on determining whether the combination of taurine and black pepper extract is an effective natural treatment for reducing cardiovascular diseases risk factors (i.e., hypertension and hyperhomocysteinemia) and for driving anti-inflammatory, antioxidative and anti-atherosclerotic mechanisms to combat coronary artery disease, heart failure, myocardial infarction, and atherosclerotic disease.


Assuntos
Doenças Cardiovasculares , Doença da Artéria Coronariana , Piper nigrum , Humanos , Doença da Artéria Coronariana/tratamento farmacológico , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Taurina/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Anti-Inflamatórios/farmacologia
5.
Biomolecules ; 13(5)2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37238657

RESUMO

Cardiovascular diseases (CVDs) are the main contributors to global morbidity and mortality. Major pathogenic phenotypes of CVDs include the development of endothelial dysfunction, oxidative stress, and hyper-inflammatory responses. These phenotypes have been found to overlap with the pathophysiological complications of coronavirus disease 2019 (COVID-19). CVDs have been identified as major risk factors for severe and fatal COVID-19 states. The renin-angiotensin system (RAS) is an important regulatory system in cardiovascular homeostasis. However, its dysregulation is observed in CVDs, where upregulation of angiotensin type 1 receptor (AT1R) signaling via angiotensin II (AngII) leads to the AngII-dependent pathogenic development of CVDs. Additionally, the interaction between the spike protein of severe acute respiratory syndrome coronavirus 2 with angiotensin-converting enzyme 2 leads to the downregulation of the latter, resulting in the dysregulation of the RAS. This dysregulation favors AngII/AT1R toxic signaling pathways, providing a mechanical link between cardiovascular pathology and COVID-19. Therefore, inhibiting AngII/AT1R signaling through angiotensin receptor blockers (ARBs) has been indicated as a promising therapeutic approach to the treatment of COVID-19. Herein, we review the role of AngII in CVDs and its upregulation in COVID-19. We also provide a future direction for the potential implication of a novel class of ARBs called bisartans, which are speculated to contain multifunctional targeting towards COVID-19.


Assuntos
COVID-19 , Doenças Cardiovasculares , Humanos , Angiotensina II , COVID-19/complicações , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/complicações , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/farmacologia
6.
Mol Cell Biochem ; 478(12): 2907-2916, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37004639

RESUMO

The renin angiotensin system is a key regulator of blood pressure homeostasis. Angiotensin type 1 (AT1R) and 2 receptors (AT2R) have been investigated as targets for cisplatin-induced acute kidney injury; however, their therapeutic potential remains inconclusive. This pilot study aimed to determined the effect that acute cisplatin treatment had on angiotensin II (AngII)-induced contraction in blood vessels and expression profiles of AT1R and AT2R in mouse arteries and kidneys. Male C57BL/6 mice at 18 week of age (n = 8) were treated with vehicle or bolus dose of cisplatin (12.5 mg/kg). Thoracic aorta (TA), adnominal aorta (AA), brachiocephalic arteries (BC), iliac arteries (IL) and kidneys were collected for isometric tension and immunohistochemistry analysis. Cisplatin treatment reduced IL contraction to AngII at all doses (p < 0.01, p < 0.001, p < 0.0001); however, AngII did not induce contraction in TA, AA or BC in either treatment group. Following cisplatin treatment, AT1R expression was significantly upregulated in the media of TA (p < 0.0001) and AA (p < 0.0001), and in the endothelium (p < 0.05) media (p < 0.0001) and adventitia (p < 0.01) of IL. Cisplatin treatment significantly reduced AT2R expression in the endothelium (p < 0.05) and media (p < 0.05) of TA. In renal tubules, both AT1R (p < 0.01) and AT2R (p < 0.05) were increased following cisplatin treatment. Herein, we report that cisplatin reduces AngII-mediated contraction in IL and may be explained by an absence of normal counterregulatory expression of AT1R and AT2R, indicating other factors are involved.


Assuntos
Angiotensina II , Cisplatino , Masculino , Camundongos , Animais , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Cisplatino/farmacologia , Projetos Piloto , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 2 de Angiotensina/metabolismo , Camundongos Endogâmicos C57BL
7.
Life Sci ; 318: 121466, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36773693

RESUMO

AIMS: Nephrotoxicity is the hallmark of anti-neoplastic drug metabolism that causes oxidative stress. External chemical agents and prescription drugs release copious amounts of free radicals originating from molecular oxidation and unless sustainably scavenged, they stimulate membrane lipid peroxidation and disruption of the host antioxidant mechanisms. This review aims to provide a comprehensive collection of potential cytoprotective remedies in surmounting the most difficult aspect of cancer therapy as well as preventing renal oxidative stress by other means. MATERIALS AND METHODS: Over 400 published research and review articles spanning several decades were scrutinised to obtain the relevant data which is presented in 3 categories; sources, mechanisms, and mitigation of renal oxidative stress. KEY-FINDINGS: Drug and chemical-induced nephrotoxicity commonly manifests as chronic or acute kidney disease, nephritis, nephrotic syndrome, and nephrosis. Renal replacement therapy requirements and mortalities from end-stage renal disease are set to rapidly increase in the next decade for which 43 different cytoprotective compounds which have the capability to suppress experimental nephrotoxicity are described. SIGNIFICANCE: The renal system performs essential homeostatic functions that play a significant role in eliminating toxicants, and its accumulation and recurrence in nephric tissues results in tubular degeneration and subsequent renal impairment. Global statistics of the latest chronic kidney disease prevalence is 13.4 % while the end-stage kidney disease requiring renal replacement therapy is 4-7 million per annum. The remedial compounds discussed herein had proven efficacy against nephrotoxicity manifested consequent to impaired antioxidant mechanisms in preclinical models produced by renal oxidative stress activators.


Assuntos
Nefropatias , Nefrose , Insuficiência Renal , Humanos , Antioxidantes/farmacologia , Rim/metabolismo , Estresse Oxidativo , Nefropatias/metabolismo , Insuficiência Renal/metabolismo , Nefrose/metabolismo
8.
Biochem Pharmacol ; 208: 115397, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36566945

RESUMO

Diminazene aceturate (DIZE), a putative angiotensin-converting enzyme 2 (ACE2) activator, elicits relaxation in various animal models. This study aimed to determine the relaxing mechanisms in internal iliac arteries utilised by DIZE in healthy and atherogenic rabbit models. Studies were conducted on internal iliac artery rings retrieved from male New Zealand White rabbits fed a 4-week healthy control (n = 24) or atherogenic diet (n = 20). To investigate pathways utilised by DIZE to promote arterial relaxation, a DIZE dose response [10-9.0 M - 10-5.0 M] was performed on pre-contracted rings incubated with pharmaceuticals that target: components of the renin-angiotensin system; endothelial- and vascular smooth muscle-dependent mechanisms; protein kinases; and potassium channels. ACE2 expression was quantified by immunohistochemistry analysis following a 2 hr or 4 hr DIZE incubation. DIZE significantly enhanced vessel relaxation in atherogenic rings at doses [10-5.5 M] (p < 0.01) and [10-5.0 M] (p < 0.0001), when compared to healthy controls. Comprehensive results from functional isometric studies determined that DIZE causes relaxation via different mechanisms depending on pathology. For the first time, we report that in healthy blood vessels DIZE exerts its direct relaxing effect through ACE2/AT2R and NO/sGC pathways; however, in atherogenesis this switches to MasR, arachidonic acid pathway (i.e., COX1/2, EET and DHET), MCLP, Ca2+ activated voltage channels, AMPK and ERK1/2. Moreover, quantitative immunohistochemical analysis demonstrated that DIZE increases artery ACE2 expression in a time dependent manner. We provide a detailed investigation of DIZE's mechanisms and demonstrate for the first time that in healthy and atherogenic arteries DIZE provides beneficial effects through directly inducing relaxation, albeit via different pathways.


Assuntos
Aterosclerose , Peptidil Dipeptidase A , Masculino , Animais , Coelhos , Peptidil Dipeptidase A/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Sistema Renina-Angiotensina , Diminazena/farmacologia , Aterosclerose/tratamento farmacológico
9.
Heliyon ; 8(9): e10608, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36158077

RESUMO

Cisplatin spearheads the anticancer chemotherapeutics in present-day use although acute toxicity is its primary impediment factor. Among a plethora of experimental medications, a drug as effective or surpassing the benefits of cisplatin has not been discovered yet. Although Oxaliplatin is considered more superior to cisplatin, the former has been better for colorectal cancer while cisplatin is widely used for treating gynaecological cancers. Carcinoma imposes a heavy toll on mortality rates worldwide despite the novel treatment strategies and detection methods that have been introduced; nanomedicine combined with precision medicine, immunotherapy, volume-regulated anion channels, and fluorodeoxyglucose-positron emission tomography. Millions of deaths occur annually from metastatic cancers which escape early detection and the concomitant diseases caused by highly toxic chemotherapy that causes organ damage. It continues due to insufficient knowledge of the debilitative mechanisms induced by cancer biology. To overcome chemoresistance and to attenuate the adverse effects of cisplatin therapy, both in vitro and in vivo models of cisplatin-treated cancers and a few multi-centred, multi-phasic, randomized clinical trials in pursuant with recent novel strategies have been tested. They include plant-based phytochemical compounds, de novo drug delivery systems, biochemical/immune pathways, 2D and 3D cell culture models using small molecule inhibitors and genetic/epigenetic mechanisms, that have contributed to further the understanding of cisplatin's role in modulating the tumour microenvironment. Cisplatin was beneficial in cancer therapy for modulating the putative cellular mechanisms; apoptosis, autophagy, cell cycle arrest and gene therapy of micro RNAs. Specific importance of drug influx, efflux, systemic circulatory toxicity, half-maximal inhibition, and the augmentation of host immunometabolism have been identified. This review offers a discourse on the recent anti-neoplastic treatment strategies to enhance cisplatin efficacy and to overcome chemoresistance, given its superiority among other tolerable chemotherapies.

10.
Biomedicines ; 10(7)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35885036

RESUMO

Diminazene aceturate (DIZE) is a putative angiotensin-converting enzyme 2 (ACE2) activator and angiotensin type 1 receptor antagonist (AT1R). Its simple chemical structure possesses a negatively charged triazene segment that is homologous to the tetrazole of angiotensin receptor blockers (ARB), which explains its AT1R antagonistic activity. Additionally, the activation of ACE2 by DIZE converts the toxic octapeptide angiotensin II (AngII) to the heptapeptides angiotensin 1-7 and alamandine, which promote vasodilation and maintains homeostatic balance. Due to DIZE's protective cardiovascular and pulmonary effects and its ability to target ACE2 (the predominant receptor utilized by severe acute respiratory syndrome coronavirus 2 to enter host cells), it is a promising treatment for coronavirus 2019 (COVID-19). To determine DIZE's ability to inhibit AngII constriction, in vitro isometric tension analysis was conducted on rabbit iliac arteries incubated with DIZE or candesartan and constricted with cumulative doses of AngII. In silico docking and ligand interaction studies were performed to investigate potential interactions between DIZE and other ARBs with AT1R and the spike protein/ACE2 complex. DIZE, similar to the other ARBs investigated, was able to abolish vasoconstriction in response to AngII and exhibited a binding affinity for the spike protein/ACE2 complex (PDB 6LZ6). These results support the potential of DIZE as a treatment for COVID-19.

11.
Biofactors ; 48(4): 813-856, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35719120

RESUMO

The therapeutic potential of the tocotrienol group stems from its nutraceutical properties as a dietary supplement. It is largely considered to be safe when consumed at low doses for attenuating pathophysiology as shown by animal models, in vitro assays, and ongoing human trials. Medical researchers and the allied sciences have experimented with tocotrienols for many decades, but its therapeutic potential was limited to adjuvant or concurrent treatment regimens. Recent studies have focused on targeted drug delivery by enhancing the bioavailability through carriers, self-sustained emulsions, nanoparticles, and ethosomes. Epigenetic modulation and computer remodeling are other means that will help increase chemosensitivity. This review will focus on the systemic intracellular anti-cancer, antioxidant, and anti-inflammatory mechanisms that are stimulated and/or regulated by tocotrienols while highlighting its potent therapeutic properties in a diverse group of clinical diseases.


Assuntos
Neoplasias , Tocotrienóis , Animais , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Suplementos Nutricionais , Humanos , Neoplasias/tratamento farmacológico , Tocotrienóis/farmacologia , Tocotrienóis/uso terapêutico , Vitamina E
12.
Viruses ; 14(5)2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35632769

RESUMO

SARS-CoV-2 is a global challenge due to its ability to mutate into variants that spread more rapidly than the wild-type virus. Because the molecular biology of this virus has been studied in such great detail, it represents an archetypal paradigm for research into new antiviral drug therapies. The rapid evolution of SARS-CoV-2 in the human population is driven, in part, by mutations in the receptor-binding domain (RBD) of the spike (S-) protein, some of which enable tighter binding to angiotensin-converting enzyme (ACE2). More stable RBD-ACE2 association is coupled with accelerated hydrolysis of furin and 3CLpro cleavage sites that augment infection. Non-RBD and non-interfacial mutations assist the S-protein in adopting thermodynamically favorable conformations for stronger binding. The driving forces of key mutations for Alpha, Beta, Gamma, Delta, Kappa, Lambda and Omicron variants, which stabilize the RBD-ACE2 complex, are investigated by free-energy computational approaches, as well as equilibrium and steered molecular dynamic simulations. Considered also are the structural hydropathy traits of the residues in the interface between SARS-CoV-2 RBD and ACE2 protein. Salt bridges and π-π interactions are critical forces that create stronger complexes between the RBD and ACE2. The trend of mutations is the replacement of non-polar hydrophobic interactions with polar hydrophilic interactions, which enhance binding of RBD with ACE2. However, this is not always the case, as conformational landscapes also contribute to a stronger binding. Arginine, the most polar and hydrophilic among the natural amino acids, is the most aggressive mutant amino acid for stronger binding. Arginine blockers, such as traditional sartans that bear anionic tetrazoles and carboxylates, may be ideal candidate drugs for retarding viral infection by weakening S-protein RBD binding to ACE2 and discouraging hydrolysis of cleavage sites. Based on our computational results it is suggested that a new generation of "supersartans", called "bisartans", bearing two anionic biphenyl-tetrazole pharmacophores, are superior to carboxylates in terms of their interactions with viral targets, suggesting their potential as drugs in the treatment of COVID-19. In Brief: This in silico study reviews our understanding of molecular driving forces that trigger mutations in the SARS-CoV-2 virus. It also reports further studies on a new class of "supersartans" referred to herein as "bisartans", bearing two anionic biphenyltetrazole moieties that show potential in models for blocking critical amino acids of mutants, such as arginine, in the Delta variant. Bisartans may also act at other targets essential for viral infection and replication (i.e., ACE2, furin cleavage site and 3CLpro), rendering them potential new drugs for additional experimentation and translation to human clinical trials.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2/genética , Arginina/genética , Furina/genética , Humanos , Glicoproteínas de Membrana/metabolismo , Mutação , Receptores Virais/metabolismo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Proteínas do Envelope Viral/genética
13.
Hepatol Commun ; 6(9): 2523-2537, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35593203

RESUMO

Splanchnic vasodilatation contributes to the development and aggravation of portal hypertension (PHT). We previously demonstrated that in cirrhosis, angiotensin- mediates splanchnic vasodilatation through the Mas receptor (MasR). In this study, we investigated whether the recently characterized second receptor for angiotensin-(1-7), Mas-related G protein-coupled receptor type D (MrgD), contributes to splanchnic vasodilatation in cirrhotic and noncirrhotic PHT. Splanchnic vascular hemodynamic and portal pressure were determined in two rat models of cirrhotic PHT and a rat model with noncirrhotic PHT, treated with either MrgD blocker D-Pro7 -Ang-(1-7) (D-Pro) or MasR blocker A779. Gene and protein expression of MrgD and MasR were measured in splanchnic vessels and livers of cirrhotic and healthy rats and in patients with cirrhosis and healthy subjects. Mesenteric resistance vessels isolated from cirrhotic rats were used in myographs to study their vasodilatory properties. MrgD was up-regulated in cirrhotic splanchnic vessels but not in the liver. In cirrhotic rats, treatment with D-Pro but not A779 completely restored splanchnic vascular resistance to a healthy level, resulting in a 33% reduction in portal pressure. Mesenteric vessels pretreated with D-Pro but not with A779 failed to relax in response to acetylcholine. There was no splanchnic vascular MrgD or MasR up-regulation in noncirrhotic PHT; thus, receptor blockers had no effect on splanchnic hemodynamics. Conclusion: MrgD plays a major role in the development of cirrhotic PHT and is a promising target for the development of novel therapies to treat PHT in cirrhosis. Moreover, neither MrgD nor MasR contributes to noncirrhotic PHT.


Assuntos
Hipertensão Portal , Receptores Acoplados a Proteínas G , Animais , Modelos Animais de Doenças , Hipertensão Portal/tratamento farmacológico , Cirrose Hepática/complicações , Proteínas do Tecido Nervoso , Pressão na Veia Porta , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/antagonistas & inibidores
14.
Comput Struct Biotechnol J ; 20: 2091-2111, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432786

RESUMO

The discovery and facile synthesis of a new class of sartan-like arterial antihypertensive drugs (angiotensin receptor blockers [ARBs]), subsequently referred to as "bisartans" is reported. In vivo results and complementary molecular modelling presented in this communication indicate bisartans may be beneficial for the treatment of not only heart disease, diabetes, renal dysfunction, and related illnesses, but possibly COVID-19. Bisartans are novel bis-alkylated imidazole sartan derivatives bearing dual symmetric anionic biphenyl tetrazole moieties. In silico docking and molecular dynamics studies revealed bisartans exhibited higher binding affinities for the ACE2/spike protein complex (PDB 6LZG) compared to all other known sartans. They also underwent stable docking to the Zn2 + domain of the ACE2 catalytic site as well as the critical interfacial region between ACE2 and the SARS-CoV-2 receptor binding domain. Additionally, semi-stable docking of bisartans at the arginine-rich furin-cleavage site of the SARS-CoV-2 spike protein (residues 681-686) required for virus entry into host cells, suggest bisartans may inhibit furin action thereby retarding viral entry into host cells. Bisartan tetrazole groups surpass nitrile, the pharmacophoric "warhead" of PF-07321332, in its ability to disrupt the cysteine charge relay system of 3CLpro. However, despite the apparent targeting of multifunctional sites, bisartans do not inhibit SARS-CoV-2 infection in bioassays as effectively as PF-07321332 (Paxlovid).

15.
Biochim Biophys Acta Rev Cancer ; 1877(2): 188699, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35192881

RESUMO

Colorectal cancer (CRC) is a malignancy in the gastro-intestinal (GI) tract which has very limited treatment options still, despite the vast amount of research undertaken. CRC was first discovered a century ago and is the third-highest cause of global cancer-related deaths. Once diagnosed as a T4 -stage carcinoma, the prognosis extends only up to two years at the best. Although resectable surgery remains the primary safeguard in combatting metastatic CRC, research had focussed on to various therapeutic and disease management strategies, such as stem cell - based therapies, CT, MRI, PET-CT scans, colonography, endoscopy and biologics. The struggle in developing an anti-cancer therapy may be due to its unresolved aetiology comprising of genetic abnormalities, and multiple risk factors in lifestyle, culture, and environment in the globally diverse, human populations. This review aims to summarize the prominent features of CRC which could encourage lifestyle changes and introduce novel clinically - relevant therapeutic strategies to improve its overall management.


Assuntos
Neoplasias Colorretais , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/terapia , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
16.
Biomolecules ; 11(7)2021 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-34356603

RESUMO

Angiotensin II (Ang II) may contain a charge relay system (CRS) involving Tyr/His/carboxylate, which creates a tyrosinate anion for receptor activation. Energy calculations were carried out to determine the preferred geometry for the CRS in the presence and absence of the Arg guanidino group occupying position 2 of Ang II. These findings suggest that Tyr is preferred over His for bearing the negative charge and that the CRS is stabilized by the guanidino group. Recent crystallography studies provided details of the binding of nonpeptide angiotensin receptor blockers (ARBs) to the Ang II type 1 (AT1) receptor, and these insights were applied to Ang II. A model of binding and receptor activation that explains the surmountable and insurmountable effects of Ang II analogues sarmesin and sarilesin, respectively, was developed and enabled the discovery of a new generation of ARBs called bisartans. Finally, we determined the ability of the bisartan BV6(TFA) to act as a potential ARB, demonstrating similar effects to candesartan, by reducing vasoconstriction of rabbit iliac arteries in response to cumulative doses of Ang II. Recent clinical studies have shown that Ang II receptor blockers have protective effects in hypertensive patients infected with SARS-CoV-2. Therefore, the usage of ARBS to block the AT1 receptor preventing the binding of toxic angiotensin implicated in the storm of cytokines in SARS-CoV-2 is a target treatment and opens new avenues for disease therapy.


Assuntos
Angiotensina II/metabolismo , Antagonistas de Receptores de Angiotensina/química , Antagonistas de Receptores de Angiotensina/farmacologia , Tratamento Farmacológico da COVID-19 , Descoberta de Drogas , Receptor Tipo 1 de Angiotensina/metabolismo , Angiotensina II/análogos & derivados , Animais , COVID-19/metabolismo , Cristalografia por Raios X , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Masculino , Modelos Moleculares , Coelhos , Receptor Tipo 1 de Angiotensina/química , Vasoconstrição/efeitos dos fármacos
17.
EPMA J ; 12(2): 155-176, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34025826

RESUMO

Cost-efficacy of currently applied treatments is an issue in overall cancer management challenging healthcare and causing tremendous economic burden to societies around the world. Consequently, complex treatment models presenting concepts of predictive diagnostics followed by targeted prevention and treatments tailored to the personal patient profiles earn global appreciation as benefiting the patient, healthcare economy, and the society at large. In this context, application of flavonoids as a spectrum of compounds and their nano-technologically created derivatives is extensively under consideration, due to their multi-faceted anti-cancer effects applicable to the overall cost-effective cancer management, primary, secondary, and even tertiary prevention. This article analyzes most recently updated data focused on the potent capacity of flavonoids to promote anti-cancer therapeutic effects and interprets all the collected research achievements in the frame-work of predictive, preventive, and personalized (3P) medicine. Main pillars considered are: - Predictable anti-neoplastic, immune-modulating, drug-sensitizing effects; - Targeted molecular pathways to improve therapeutic outcomes by increasing sensitivity of cancer cells and reversing their resistance towards currently applied therapeutic modalities.

18.
Cancers (Basel) ; 13(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805488

RESUMO

Administration of the chemotherapeutic agent cisplatin leads to acute kidney injury (AKI). Cisplatin-induced AKI (CIAKI) has a complex pathophysiological map, which has been linked to cellular uptake and efflux, apoptosis, vascular injury, oxidative and endoplasmic reticulum stress, and inflammation. Despite research efforts, pharmaceutical interventions, and clinical trials spanning over several decades, a consistent and stable pharmacological treatment option to reduce AKI in patients receiving cisplatin remains unavailable. This has been predominately linked to the incomplete understanding of CIAKI pathophysiology and molecular mechanisms involved. Herein, we detail the extensively known pathophysiology of cisplatin-induced nephrotoxicity that manifests and the variety of pharmacological and genetic alteration studies that target them.

19.
Mol Metab ; 49: 101205, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33684607

RESUMO

BACKGROUND: The bone-derived protein osteocalcin (OC), in its undercarboxylated (ucOC) form, has a beneficial effect on energy metabolism and may be a future therapeutic target for metabolic diseases. Increasing evidence suggests a link between ucOC and cardiovascular disease (CVD) development; however, the exact relationship is conflicting and unclear. SCOPE OF REVIEW: The aim of this review was to summarise the current research examining the interaction between OC and vascular dysfunction, the initiating stage in the development of atherosclerosis and CVD. MAJOR CONCLUSIONS: In humans, the association between OC and vascular function is inconsistent. Several studies report that total OC (tOC) is associated with adverse function or beneficial function, whereas others report that tOC and ucOC has no effect on vascular function. The conflicting data are likely due to several methodological inconsistencies, in particular the lack of studies reporting circulating ucOC levels. In animal models, the direct administration of ucOC to isolated blood vessels ex vivo produced minimal changes in endothelial function, but importantly, no adverse responses. Finally, in human endothelial and vascular smooth muscle cells, ucOC treatment did not influence classical markers of cellular function, including endothelin-1, vascular adhesion molecule-1 and monocyte chemoattractant protein-1 after exposure to high glucose and inflammatory conditions. The lack of adverse effects in ex vivo and in vitro studies suggests that ucOC may be targeted as a future therapeutic for metabolic diseases, without the risk of detrimental effects in the vasculature. However, further studies are needed to confirm these findings and to investigate whether there is a direct beneficial influence of ucOC.


Assuntos
Biomarcadores/sangue , Fenômenos Fisiológicos Cardiovasculares , Osteocalcina/sangue , Animais , Aterosclerose , Osso e Ossos , Doenças Cardiovasculares , Células Endoteliais , Humanos , Receptores Acoplados a Proteínas G/metabolismo
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