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1.
Small ; : e2403629, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958098

RESUMO

Natural organisms have evolved precise sensing systems relying on unique ion channels, which can efficiently perceive various physical/chemical stimuli based on ionic signal transmission in biological fluid environments. However, it is still a huge challenge to achieve extensive applications of the artificial counterparts as an efficient wet sensing platform due to the fluidity of the working medium. Herein, nanofluidic membranes with selective cation transport properties and solid-state organic electrochemical transistors (OECTs) with amplified signals are integrated together to mimic human gustatory sensation, achieving ionic gustatory reagent recognition and a portable configuration. Cu-HHTP nanofluidic membranes with selective cation transport through their uniform micropores are constructed first, followed by assembly with OECTs to form the designed nanofluidic membrane-assisted OECTs (nanofluidic OECTs). As a result, they can distinguish typically ionic gustatory reagents, and even ionic liquids (ILs), demonstrating enhanced gustatory perception performance under a wide concentration range (10-7-10-1 m) compared with those of conventional OECTs. The linear correlations between the response and the reagent concentration further indicate the promising potential for practical application as a next-generation sensing platform. It is suggested that nanofluidic membranes mediated intramembrane cation transport based on the steric hindrance effect, resulting in distinguishable and improved response to multiple ions.

2.
Cells ; 13(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38920639

RESUMO

The polarised expression of specific transporters in proximal tubular epithelial cells is important for the renal clearance of many endogenous and exogenous compounds. Thus, ideally, the in vitro tools utilised for predictions would have a similar expression of apical and basolateral xenobiotic transporters as in vivo. Here, we assessed the functionality of organic cation and anion transporters in proximal tubular-like cells (PTL) differentiated from human induced pluripotent stem cells (iPSC), primary human proximal tubular epithelial cells (PTEC), and telomerase-immortalised human renal proximal tubular epithelial cells (RPTEC/TERT1). Organic cation and anion transport were studied using the fluorescent substrates 4-(4-(dimethylamino)styryl)-N-methylpyridinium iodide (ASP) and 6-carboxyfluorescein (6-CF), respectively. The level and rate of intracellular ASP accumulation in PTL following basolateral application were slightly lower but within a 3-fold range compared to primary PTEC and RPTEC/TERT1 cells. The basolateral uptake of ASP and its subsequent apical efflux could be inhibited by basolateral exposure to quinidine in all models. Of the three models, only PTL showed a modest preferential basolateral-to-apical 6-CF transfer. These results show that organic cation transport could be demonstrated in all three models, but more research is needed to improve and optimise organic anion transporter expression and functionality.


Assuntos
Células Epiteliais , Túbulos Renais Proximais , Humanos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/citologia , Células Epiteliais/metabolismo , Modelos Biológicos , Compostos de Piridínio/metabolismo , Ânions/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Transporte Biológico , Transportadores de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos/genética , Linhagem Celular , Cátions/metabolismo , Fluoresceínas/metabolismo , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Proteínas de Transporte de Cátions Orgânicos/genética
3.
J Pharmacol Exp Ther ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777603

RESUMO

Metformin's potential in treating ischemic stroke and neurodegenerative conditions is of growing interest. Yet, the absence of established systemic and brain pharmacokinetic (PK) parameters at relevant pre-clinical doses presents a significant knowledge gap. This study highlights these PK parameters and the importance of using pharmacologically relevant pre-clinical doses to study pharmacodynamics (PD) in stroke and related neurodegenerative diseases. An LC-MS/MS method to measure metformin levels in plasma, brain, and cerebrospinal fluid (CSF) was developed and validated. In vitro assays examined brain tissue binding and metabolic stability. Intravenous (IV) bolus administration of metformin to C57BL6 mice covered low to high dose range maintaining pharmacological relevance. Quantification of metformin in the brain was used to assess brain pharmacokinetic parameters, such as unidirectional blood-to-brain constant (Kin) and unbound brain-to-plasma ratio (Kp, uu, brain). Metformin exhibited no binding in the mouse plasma and brain and remained metabolically stable. It rapidly entered the brain, reaching detectable levels in as little as 5 minutes. A Kin value of 1.87 {plus minus} 0.27 µl/g/min was obtained. As the dose increased, Kp, uu, brain showed decreased value, implying saturation, but this did not affect an increase in absolute brain concentrations. Metformin was quantifiable in the CSF at 30 minutes but decreased over time, with concentrations lower than those in the brain across all doses. Our findings emphasize the importance of metformin dose selection based on pharmacokinetic parameters for pre-clinical pharmacological studies. We anticipate further investigations focusing on pharmacokinetics and pharmacodynamics (PKPD) in disease conditions, such as stroke. Significance Statement The study establishes crucial pharmacokinetic parameters of metformin for treating ischemic stroke and neurodegenerative diseases, addressing a significant knowledge gap. It further emphasizes the importance of selecting pharmacologically relevant pre-clinical doses. The findings highlight metformin's rapid brain entry, minimal binding, and metabolic stability. The necessity of considering pharmacokinetic parameters in pre-clinical studies provides a foundation for future investigations into metformin's efficacy for neurodegenerative disease (s).

4.
Stroke ; 55(1): 190-202, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134249

RESUMO

Drug development for ischemic stroke is challenging as evidenced by the paucity of therapeutics that have advanced beyond a phase III trial. There are many reasons for this lack of clinical translation including factors related to the experimental design of preclinical studies. Often overlooked in therapeutic development for ischemic stroke is the requirement of effective drug delivery to the brain, which is critical for neuroprotective efficacy of several small and large molecule drugs. Advancing central nervous system drug delivery technologies implies a need for detailed comprehension of the blood-brain barrier (BBB) and neurovascular unit. Such knowledge will permit the innate biology of the BBB/neurovascular unit to be leveraged for improved bench-to-bedside translation of novel stroke therapeutics. In this review, we will highlight key aspects of BBB/neurovascular unit pathophysiology and describe state-of-the-art approaches for optimization of central nervous system drug delivery (ie, passive diffusion, mechanical opening of the BBB, liposomes/nanoparticles, transcytosis, intranasal drug administration). Additionally, we will discuss how endogenous BBB transporters represent the next frontier of drug delivery strategies for stroke. Overall, this review will provide cutting edge perspective on how central nervous system drug delivery must be considered for the advancement of new stroke drugs toward human trials.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Sistemas de Liberação de Medicamentos , Acidente Vascular Cerebral/tratamento farmacológico , Fármacos do Sistema Nervoso Central/farmacologia , Barreira Hematoencefálica
5.
J Med Food ; 26(11): 849-857, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37889606

RESUMO

The transport of cations in the cardiomyocytes, crucial for the functioning of the heart, can be affected by walnut diet due to the high content of polyunsaturated fatty acids. Healthy and metabolically compromised rats (drinking 10% fructose solution) were subjected to a diet supplemented with 2.4 g of walnuts for 6 weeks to investigate the effect on proteins involved in cation transport in the heart cells. Fructose increased the level of the α1 subunit of Na+/K+-ATPase and the phosphorylation of extracellular signal-regulated kinase 1/2 in the heart of control and walnut-eating rats, while elevated L-type calcium channel α (LTCCα), sodium-calcium exchanger 1 (NCX1), and Maxi Kα level were observed only in rats that did not consume walnuts. However, walnuts significantly increased the cardiac content of LTCC, NCX1, and Maxi Kα, as well as Kir6.1 and SUR2B subunits of KATP channel, but only in fructose-naive rats. In animals that drank fructose, a significant increasing effect of walnuts was observed only in Akt kinase phosphorylation, which may be a part of the antiarrhythmic mechanism of decreasing cation currents in cardiomyocytes. The walnut diet-induced increase in LTCC and NCX1 expression in healthy rats may indicate intense cardiac calcium turnover, whereas the effect on Kir6.1 and SUR2B subunits suggests stimulation of KATP channel transport in the cardiac vasculature. The effects of walnuts on the cation-handling proteins in the heart, mostly limited to healthy animals, suggest the possible use of a walnut-supplemented diet in the prevention rather than the treatment of cardiological channelopathies.


Assuntos
Juglans , Ratos , Masculino , Animais , Dieta , Cátions , Frutose , Trifosfato de Adenosina
6.
J Cancer ; 14(8): 1309-1320, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283797

RESUMO

An imbalance in ROS (reactive oxidative species) and the antioxidant barrier regulates the process of tumorigenesis. GSH has a key effect in preventing cells from oxidative damage by scavenging ROS. The role of CHAC2, an enzyme regulating GSH, in lung adenocarcinoma remains unknown. Here, RNA sequencing data analysis and immunohistochemistry (IHC) assays of lung adenocarcinoma and normal lung tissues were used to verify the expression of CHAC2. The effect of CHAC2 on the proliferation abilities of lung adenocarcinoma cells was examined using a series of overexpression or knockout assays. RNA sequencing and IHC results showed that the expression level of CHAC2 in lung adenocarcinoma was higher than that in normal lung tissues. CCK-8, colony formation and subcutaneous xenograft experiments in BALB/c nude mice showed that in vitro and in vivo CHAC2 promoted the growth capacity of lung adenocarcinoma cells. Subsequent immunoblot, immunohistochemistry and flow cytometry experiments showed that CHAC2 increased ROS by reducing GSH in lung adenocarcinoma and that the elevated ROS activated the MAPK pathway. Our investigation identified a new role for CHAC2 and elucidated the mechanism by which CHAC2 promotes lung adenocarcinoma progression.

7.
Biochim Biophys Acta Biomembr ; 1865(7): 184182, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37276926

RESUMO

The ionophoric antibiotic salinomycin is in the phase of preclinical tests against several types of malignant tumors including breast cancer. Notwithstanding, the data on its ion selectivity, although being critical for its therapeutic activity, are rather scarce. In the present work, we studied the ability of salinomycin to exert cation/H+-exchange across artificial bilayer lipid membranes (BLM) by measuring electrical potential on planar BLM in the presence of a protonophore and fluorescence responses of the pH-sensitive dye pyranine entrapped in liposomes. The following order of ion selectivity was obtained by these two methods: K+ > Na+ > Rb+ > Cs+ > Li+. Measurements of the monovalent cation-induced quenching of fluorescence of thallium ions in methanol showed that salinomycin effectively binds potassium and calcium but poorly binds sodium and lithium ions. At high concentrations, salinomycin transports Ca2+ through membranes of liposomes and mitochondria, as measured by using the calcium-sensitive dye Fluo-5 N. The data obtained can be used in the mechanistic studies of the anti-tumor activity of salinomycin and its selective cytotoxicity towards cancer stem cells.


Assuntos
Antibacterianos , Lipossomos , Antibacterianos/farmacologia , Cálcio , Bicamadas Lipídicas , Lítio/metabolismo , Cátions , Sódio/metabolismo
8.
ACS Appl Mater Interfaces ; 15(14): 17767-17778, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37011231

RESUMO

Conjugated polymers (CPs) that show stable and reversible cation insertion/deinsertion under ambient conditions hold great potential for optoelectronic and energy storage devices. However, n-doped CPs are prone to parasitic reactions upon exposure to moisture or oxygen. This study reports a new family of napthalenediimide (NDI) based conjugated polymers capable of undergoing electrochemical n-type doping in ambient air. By functionalizing the NDI-NDI repeating unit with alternating triethylene glycol and octadecyl side chains, the polymer backbone shows stable electrochemical doping at ambient conditions. We systematically investigate the extent of volumetric doping involving monovalent cations of varying size (Li+, Na+, tetraethylammonium (TEA+)) with electrochemical methods, including cyclic voltammetry, differential pulse voltammetry, spectroelectrochemistry, and electrochemical impedance spectroscopy. We observed that introducing hydrophilic side chains on the polymer backbone improves the local dielectric environment of the backbones and lowers the energetic barrier for ion insertion. Surprisingly, when using Na+ electrolyte, the polymer films exhibit higher volumetric doping efficiency, faster-switching kinetics, higher optical contrast, and selective multielectrochromism when compared to Li+ or TEA+ electrolytes. Using well-tempered metadynamics, we characterize the free energetics of side chain-ion interactions to find that Li+ binds more tightly to the glycolated NDI moieties than Na+, hindering Li+ ion transport, switching kinetics, and limiting the films' doping efficiency.

9.
medRxiv ; 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36778463

RESUMO

Background: Brain arterial diameters are novel imaging biomarkers of cerebrovascular disease, cognitive decline and dementia. Traditional vascular risk factors have been associated with brain arterial diameters but whether there may be genetic determinants of brain arterial diameters is unknown. Results: We studied 4150 participants from six geographically diverse population-based cohorts (40% European, 14% African, 22% Hispanic, 24% Asian ancestries). We measured brain arterial diameters for 13 segments and averaged them to obtain a global measure of brain arterial diameters as well as the posterior and anterior circulations. A genome-wide association study (GWAS) revealed 14 variants at one locus associated with global brain arterial diameter at genome-wide significance (P<5×10-8) (top SNP, rs7921574; ß =0.06, P=1.54×10-8). This locus mapped to an intron of CNNM2. A trans-ancestry GWAS meta-analysis identified two more loci at NT5C2 (rs10748839; P=2.54×10-8) and at AS3MT (rs10786721; P=4.97×10-8), associated with global brain arterial diameter. In addition, two SNPs co-localized with expression of CNNM2 (rs7897654, ß=0.12, P=6.17×10-7) and AL356608.1 (rs10786719, ß =-0.17, P=6.60×10-6) in brain tissue. For the posterior brain arterial diameter, two variants at one locus mapped to an intron of TCF25 were identified (top SNP, rs35994878; ß =0.11, P=2.94×10-8). For the anterior brain arterial diameter, one locus at ADAP1 was identified in trans-ancestry genome-wide association analysis (rs34217249; P=3.11×10-8). Conclusion: Our study reveals three novel risk loci (CNNM2, NT5C2 and AS3MT) associated with brain arterial diameters. Our finding may elucidate the mechanisms by which brain arterial diameters influence the risk of stroke and dementia.

10.
Curr Protein Pept Sci ; 24(3): 215-228, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36617712

RESUMO

The lens is a transparent, biconvex anatomical structure of the eyes responsible for light transmission and fine focusing on the retina. It is fundamentally constituted by water-soluble proteins called crystallins which are responsible for lens transparency due to their stable and highly organized disposition in the lens fiber cells. Some conformational changes and the subsequent aggregation of crystallins lead to loss of transparency in the lens and are the beginning of cataracts, which is the most frequent cause of reversible blindness in the world. Ultraviolet radiation is considered one of the risk factors for cataract development. The lens is exposed to radiation between 295 and 400 nm. This UV radiation may induce several processes that destroy the crystallins; the most significant is the oxidative stress due to increased free radicals formation. The oxidative stress is directly involved in modifications of the crystallin proteins leading to the formation of high molecular weight aggregates and then the subsequent opacification of the lens, known as cataracts. This review aims to summarize current knowledge about the damage of the lens proteins caused by ultraviolet radiation and its role in developing cataracts.


Assuntos
Catarata , Cristalinas , Cristalino , Humanos , Raios Ultravioleta/efeitos adversos , Cristalino/química , Cristalino/metabolismo , Cristalino/efeitos da radiação , Catarata/etiologia , Catarata/metabolismo , Cristalinas/análise , Cristalinas/química , Cristalinas/metabolismo
11.
J Biol Chem ; 299(2): 102811, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36539036

RESUMO

The Na+/K+-ATPase is an integral plasma membrane glycoprotein of all animal cells that couples the exchange of intracellular Na+ for extracellular K+ to the hydrolysis of ATP. The asymmetric distribution of Na+ and K+ is essential for cellular life and constitutes the physical basis of a series of fundamental biological phenomena. The pumping mechanism is explained by the Albers-Post model. It involves the presence of gates alternatively exposing Na+/K+-ATPase transport sites to the intracellular and extracellular sides and includes occluded states in which both gates are simultaneously closed. Unlike for K+, information is lacking about Na+-occluded intermediates, as occluded Na+ was only detected in states incapable of performing a catalytic cycle, including two Na+-containing crystallographic structures. The current knowledge is that intracellular Na+ must bind to the transport sites and become occluded upon phosphorylation by ATP to be transported to the extracellular medium. Here, taking advantage of epigallocatechin-3-gallate to instantaneously stabilize native Na+-occluded intermediates, we isolated species with tightly bound Na+ in an enzyme able to perform a catalytic cycle, consistent with a genuine occluded state. We found that Na+ becomes spontaneously occluded in the E1 dephosphorylated form of the Na+/K+-ATPase, exhibiting positive interactions between binding sites. In fact, the addition of ATP does not produce an increase in Na+ occlusion as it would have been expected; on the contrary, occluded Na+ transiently decreases, whereas ATP lasts. These results reveal new properties of E1 intermediates of the Albers-Post model for explaining the Na+ transport pathway.


Assuntos
Biocatálise , ATPase Trocadora de Sódio-Potássio , Sódio , Animais , Trifosfato de Adenosina/metabolismo , Membrana Celular/metabolismo , Cinética , Potássio/metabolismo , Sódio/metabolismo , ATPase Trocadora de Sódio-Potássio/química , ATPase Trocadora de Sódio-Potássio/metabolismo , Transporte de Íons , Fosforilação , Cátions Monovalentes/metabolismo
12.
Biochemistry (Mosc) ; 87(8): 731-741, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36171654

RESUMO

This review provides a brief description of the structure and transport function of the recently discovered family of retinal-containing Na+-translocating rhodopsins. The main emphasis is put on the kinetics of generation of electric potential difference in the membrane during a single transporter turnover. According to the proposed transport mechanism of Na+-rhodopsin, the driving force for the Na+ translocation from the cytoplasm is the local electric field created by the H+ movement from the Schiff base.


Assuntos
Rodopsina , Bases de Schiff , Transporte de Íons , Íons , Luz , Proteínas de Membrana Transportadoras , Rodopsina/química , Sódio/metabolismo
13.
Cell Calcium ; 106: 102639, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36027648

RESUMO

The bifunctional cation channel/kinase TrpM7 is ubiquitously expressed and regulates embryonic development and pathogenesis of several common diseases. The TrpM7 integral membrane ion channel domain regulates transmembrane movement of divalent cations, and its kinase domain controls gene expression via histone phosphorylation. Mechanisms regulating TrpM7 are elusive. It exists in two populations in the cell: at the cell surface where it controls divalent cation fluxes, and in intracellular vesicles where it controls zinc uptake and release. Here we report that TrpM7 is palmitoylated at a cluster of cysteines at the C terminal end of its Trp domain. Palmitoylation controls the exit of TrpM7 from the endoplasmic reticulum and the distribution of TrpM7 between cell surface and intracellular pools. Using the Retention Using Selective Hooks (RUSH) system, we demonstrate that palmitoylated TrpM7 traffics from the Golgi to the surface membrane whereas non-palmitoylated TrpM7 is sequestered in intracellular vesicles. We identify the Golgi-resident enzyme zDHHC17 and surface membrane-resident enzyme zDHHC5 as responsible for palmitoylating TrpM7 and find that TrpM7-mediated transmembrane calcium uptake is significantly reduced when TrpM7 is not palmitoylated. The closely related channel/kinase TrpM6 is also palmitoylated on the C terminal side of its Trp domain. Our findings demonstrate that palmitoylation controls ion channel activity of TrpM7 and that TrpM7 trafficking is dependant on its palmitoylation. We define a new mechanism for post translational modification and regulation of TrpM7 and other Trps.


Assuntos
Lipoilação , Canais de Cátion TRPM , Cálcio/metabolismo , Cátions/metabolismo , Fosforilação , Transdução de Sinais , Canais de Cátion TRPM/metabolismo
14.
Drug Metab Dispos ; 2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35644529

RESUMO

Facilitated transport is necessitated for large size, charged, and/or hydrophilic drugs to move across the membrane. The drug transporters in the solute carrier (SLC) superfamily, mainly including organic anion-transporting polypeptides (OATPs), organic anion transporters (OATs), organic cation transporters (OCTs), organic cation/carnitine transporters (OCTNs), peptide transporters (PEPTs), and multidrug and toxin extrusion proteins (MATEs), are critical facilitators of drug transport and distribution in human body. The expression of these SLC drug transporters is found in tissues throughout the body, with high abundance in the epithelial cells of major organs for drug disposition, such as intestine, liver, and kidney. These SLC drug transporters are clinically important in drug absorption, metabolism, distribution, and excretion. The mechanisms underlying their regulation have been revealing in recent years. Epigenetic and nuclear receptor-mediated transcriptional regulation of SLC drug transporters have particularly attracted much attention. This review focuses on the transcriptional regulation of major SLC drug transporter genes. Revealing the mechanisms underlying the transcription of those critical drug transporters will help us understand pharmacokinetics and pharmacodynamics, ultimately improving drug therapeutic effectiveness while minimizing drug toxicity. Significance Statement It has become increasingly recognized that solute carrier (SLC) drug transporters play a crucial, and sometimes determinative, role in drug disposition and response, which is reflected in decision-making during not only clinical drug therapy but also drug development. Understanding the mechanisms accounting for the transcription of these transporters is critical to interpret their abundance in various tissues under different conditions, which is necessary to clarify the pharmacological response, adverse effects, and drug-drug interactions for clinically used drugs.

15.
Curr Drug Metab ; 23(1): 82-87, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35049428

RESUMO

BACKGROUND: HER2 over-expression plays a crucial role in the cancer treatment protocol. This study evaluates the effectiveness of organic anion and cation transport inhibitors and substrate on the tumor uptake of 99mTc- HYNIC-(Ser)3-LTVPWY radiotracer in SKOV-3 tumor-bearing nude mice. METHODS: Before the injection of the radiolabeled peptide, SKOV-3 tumor-bearing nude mice were treated with furosemide, cimetidine, para-amino hippuric acid, and saline. The inhibition effects of the organic anion and cation transport inhibitors were compared with the control group. In both treatment and control groups, the tumor and renal accumulation of radiopeptide in mice bearing SKOV-3 tumors were assessed in biodistribution and SPECT imaging studies. RESULTS: The biodistribution and imaging results suggested that all treated groups showed a higher tumor and higher normal tissue radioactivity compared to the control group. According to the tumor imaging study, the furosemidetreated group had slightly better tumor uptake and a higher tumor to muscle uptake ratio than other treatment groups. CONCLUSION: Administration of furosemide (an OAT inhibitor) increased radioactivity accumulation in the kidneys and blood and improved tumor radioactivity uptake. PAH (an anion transporter substrate) and cimetidine (an OCT inhibitor) have a minor effect on the accumulation of radioactivity in the kidneys and the acquired images.


Assuntos
Furosemida , Neoplasias , Animais , Cátions , Cimetidina/farmacologia , Humanos , Transporte de Íons , Rim , Camundongos , Camundongos Nus , Peptídeos/farmacocinética , Distribuição Tecidual
16.
Biotech Histochem ; 97(3): 185-191, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33998937

RESUMO

Cisplatin is a chemotherapeutic medication that also exhibits toxic effects on normal cells. Acacetin (ACA) is an herbal compound that exhibits anticancer properties with few side effects. We investigated the use and side effects of ACA and cisplatin on the male reproductive system. Mature male mice were divided into six groups: control group treated with DMSO, cisplatin group treated with 1 mg/kg cisplatin and three ACA groups treated with 10, 25 or 50 mg/kg ACA. All treatments were applied for three days. A final experimental group was treated with 50 mg/kg ACA for 10 days. At the end of the experiment, animals were sacrificed and reactive oxygen species (ROS), total antioxidant capacity (TAC), OCTN3 gene expression and apoptosis were measured in testis. TAC and OCTN3 gene expression were decreased, while ROS and apoptosis were increased in cisplatin group compared to other groups. All ACA groups exhibited decreased apoptosis and ROS levels, and increased TAC and OCTN3 gene expression compared to the cisplatin treated mice. ACA caused fewer adverse effects in testicular tissue than cisplatin. ACA appears to improve the oxidant-antioxidant system, accelerates cell regeneration and inhibits apoptosis.


Assuntos
Antioxidantes , Cisplatino , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Apoptose , Cisplatino/farmacologia , Flavonas , Masculino , Camundongos , Testículo
17.
Methods Mol Biol ; 2402: 81-92, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34854037

RESUMO

Swept frequency electrical impedance spectroscopy (EIS) can be used in conjunction with tethered bilayer lipid membranes to monitor the membrane permeability of ions in real-time (Deplazes et al. J Phys Chem Lett 11:6353-6358, 2020). Conductance readings, as determined by EIS, are a measure of the ability of ions to be transported across membranes. Recording the change in conductance as a function of cation concentration and a comparison between a range of cations permits conclusions to be made about the specificity of cation transport through pores. An estimate for upper pore size and cation selectivity of ion channels can be established using this method.


Assuntos
Bicamadas Lipídicas , Cátions , Espectroscopia Dielétrica , Canais Iônicos , Peptídeos
18.
Drug Metab Dispos ; 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34921098

RESUMO

The human Solute Carrier 22 family (SLC22), also termed the organic ion transporter family, consists of 28 distinct multi-membrane spanning proteins, which phylogenetically cluster together according to their charge specificity for organic cations (OCTs), organic anions (OATs) and organic zwitterion/cations (OCTNs). Some SLC22 family members are well characterized in terms of their substrates, transport mechanisms and expression patterns, as well as their roles in human physiology and pharmacology, whereas others remain orphans with no known ligands. Pharmacologically, SLC22 family members play major roles as determinants of the absorption and disposition of many prescription drugs, and several including the renal transporters, OCT2, OAT1 and OAT3 are targets for many clinically important drug-drug interactions. In addition, mutations in some of these transporters (SLC22A5 (OCTN2) and SLC22A12 (URAT1) lead to rare monogenic disorders. Genetic polymorphisms in SLC22 transporters have been associated with common human disease, drug response and various phenotypic traits. Three members in this family were deorphaned in very recently: SLC22A14, SLC22A15 and SLC22A24, and found to transport specific compounds such as riboflavin (SLC22A14), anti-oxidant zwitterions (SLC22A15) and steroid conjugates (SLC22A24). Their physiologic and pharmacological roles need further investigation. This review aims to summarize the substrates, expression patterns and transporter mechanisms of individual SLC22 family members and their roles in human disease and drug disposition and response. Gaps in our understanding of SLC22 family members are described. Significance Statement In recent years, three members of the SLC22 family of transporters have been deorphaned and found to play important roles in the transport of diverse solutes. New research has furthered our understanding of the mechanisms, pharmacological roles, and clinical impact of SLC22 transporters. This minireview provides overview of SLC22 family members of their physiologic and pharmacologic roles, the impact of genetic variants in the SLC22 family on disease and drug response, and summary of recent studies deorphaning SLC22 family members.

19.
Polymers (Basel) ; 13(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34685291

RESUMO

Dendronized polyethers give rise to columnar LC structures which can successfully act as cation transport materials. Therefore, we prepared two different materials, based on Poly(epichlorohydrin-co-ethylene oxide) (PECH-co-EO) grafted with methyl 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy] benzoate, containing 20% or 40% modified units, respectively. The obtained polymers were characterized by differential scanning calorimetry (DSC), X-ray diffraction and optical microscopy between crossed polars (POM) and compared to the unmodified PECH-co-EO. In order to reach efficient transport properties, homeotropically oriented membranes were prepared by a fine-tuned thermal annealing treatment and were subsequently investigated by dynamic mechanical thermal analysis (DMTA) and dielectric thermal analysis (DETA). We found that the presence of the dendrons induces a main chain partial crystallization of the polyether chain and coherently increases the polymer Tg. This effect is more evident in the oriented membranes. As for copolymer orientation upon annealing, the cooling rate and the annealing temperature were the most crucial factors. DMTA and DETA confirmed that grafting with the dendron strongly hinders copolymer motions, but did not show great differences between unoriented and oriented membranes, regardless of the amount of dendrons.

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