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1.
Sci Rep ; 14(1): 3620, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38351156

RESUMO

Pharmacological activation of hypoxia-inducible factor 1 (HIF-1), a hypoxia-responsive transcription factor, has attracted increasing attention due to its efficacy not only in renal anemia but also in various disease models. Our study demonstrated that a HIF-1 activator enhanced extracellular vesicle (EV) production from cultured endothelial cells synergistically with adiponectin, an adipocyte-derived factor, through both transcriptional induction and posttranscriptional stabilization of an adiponectin binding partner, T-cadherin. Increased EV levels were observed in wild-type mice but not in T-cadherin null mice after consecutive administration of roxadustat. Adiponectin- and T-cadherin-dependent increased EV production may be involved in the pleiotropic effects of HIF-1 activators.


Assuntos
Adiponectina , Caderinas , Vesículas Extracelulares , Camundongos , Animais , Fator 1 Induzível por Hipóxia , Células Endoteliais , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Ativação Transcricional
2.
J Biol Chem ; 299(9): 105114, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37524131

RESUMO

Exosomes, extracellular vesicles (EVs) produced within cells, mediate both the disposal of intracellular waste and communication with distant cells, and they are involved in a variety of disease processes. Although disease modifications of exosome cargos have been well studied, it has been poorly investigated how disease processes, such as endoplasmic reticulum (ER) stress, affect EV production. We previously reported that adiponectin, an adipocyte-secreted salutary factor, increases systemic exosome levels through T-cadherin-mediated enhancement of exosome biogenesis. In the present study, we demonstrated that adiponectin/T-cadherin-dependent EV production was susceptible to ER stress and that low-dose tunicamycin significantly reduced EV production in the presence, but not in the absence, of adiponectin. Moreover, pharmacological or genetic activation of inositol-requiring enzyme 1α, a central regulator of ER stress, downregulated T-cadherin at the mRNA and protein levels as well as attenuated EV production. In addition, adiponectin/T-cadherin-independent EV production was attenuated under ER stress conditions. Repeated administration of tunicamycin to mice decreased circulating small EVs without decreasing tissue T-cadherin expression. Mechanistically, inositol-requiring enzyme 1α activation by silencing of the X-box binding protein 1 transcription factor upregulated the canonical interferon pathway and decreased EV production. The interferon pathway, when it was activated by polyinosinic-polycytidylic acid, also significantly attenuated EV production. Thus, we concluded that ER stress decreases exosome production through adiponectin/T-cadherin-dependent and -independent pathways.


Assuntos
Adiponectina , Caderinas , Estresse do Retículo Endoplasmático , Exossomos , Animais , Camundongos , Adiponectina/metabolismo , Caderinas/biossíntese , Caderinas/genética , Caderinas/metabolismo , Exossomos/efeitos dos fármacos , Exossomos/metabolismo , Inositol/metabolismo , Interferons/imunologia , Poli I-C/imunologia , Tunicamicina/farmacologia
3.
Endocr J ; 70(6): 635-645, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37062722

RESUMO

The fat-derived factor, adiponectin, is considered a salutary circulating factor. We recently demonstrated that native adiponectin binds T-cadherin and promotes intracellular biogenesis and secretion of the exosome. Exosomes play important roles in various aspects of homeostasis, including glucose and energy metabolism. However, it remains unclear whether and how the promotion of exosome production by adiponectin in vivo is beneficial for glucose and lipid metabolism. In the present study, overexpression of human adiponectin in mice resulted in an increased number of circulating exosomes, but it did not significantly improve glucose metabolism, change body weights, or change triglyceride clearance under a high-fat diet. Multiple small doses of streptozotocin increased blood glucose and decreased triglyceride clearance similarly in both wild-type and transgenic mice. Thus, these results indicated that human adiponectin overexpression in mice increases plasma exosomes but does not significantly influence glucose and lipid metabolism.


Assuntos
Exossomos , Glucose , Camundongos , Animais , Humanos , Glucose/metabolismo , Metabolismo dos Lipídeos/genética , Adiponectina/genética , Exossomos/genética , Exossomos/metabolismo , Camundongos Transgênicos , Triglicerídeos/metabolismo
4.
Angew Chem Int Ed Engl ; 62(16): e202301346, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36793254

RESUMO

We have developed the Rh+ /H8 -binap-catalyzed chemo-, regio-, diastereo-, and enantioselective intermolecular [2+2+2] cycloaddition of three unsymmetric 2π components. Thus, two arylacetylenes react with a cis-enamide to yield a protected chiral cyclohexadienylamine. Moreover, replacing one arylacetylene with a silylacetylene enables the [2+2+2] cycloaddition of three distinct unsymmetric 2π components. These transformations proceed with excellent selectivity (complete regio- and diastereoselectivity and up to >99 % yield and >99 % ee). Mechanistic studies suggest the chemo- and regioselective formation of a rhodacyclopentadiene intermediate from the two terminal alkynes.

5.
J Endocr Soc ; 6(3): bvac009, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35187382

RESUMO

Primary aldosteronism (PA) is a state of renin-independent aldosterone secretion that can range from subclinical to overt. Some normotensive individuals for whom PA screening is not routinely recommended are reported to fulfill the loading test criterion used for the diagnosis of PA. Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by the development of various endocrine tumors. Cases of PA associated with MEN1 have been reported; however, there has been no previous report on renin-independent aldosterone secretion within a family with MEN1. Herein, we present the case of a normotensive family presenting with both MEN1 and renin-independent aldosterone secretion. A 49-year-old man was admitted to our hospital for PA evaluation owing to the plasma aldosterone concentration/plasma renin activity ratio being greater than the screening cut-off value; the patient was normotensive. The patient had a history of left nephrectomy and adrenalectomy for left renal carcinoma and adrenal tumor at the age of 39 years. Subsequently, he was diagnosed with MEN1 concurrent with primary hyperparathyroidism, insulinoma, and novel MEN1 gene mutations (c.655-5_655-4insC and c.818delC). The loading tests for PA confirmation, including saline infusion, and furosemide upright and captopril challenge tests, yielded positive findings, confirming a case of renin-independent aldosterone secretion. The patient's mother, brother, and sister were also genetically or clinically diagnosed with MEN1. All of them were also normotensive and confirmed to have renin-independent aldosterone secretion. The coexistence of renin-independent aldosterone secretion and MEN1 within this family suggests a relationship between the 2 entities.

6.
Intern Med ; 60(6): 905-910, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33716254

RESUMO

Hypoglycemia should be avoided when treating patients with diabetes. Repaglinide is an insulin secretagogue with a low hypoglycemic risk because of its rapid- and short-acting effects. However, its blood concentration has been reported to increase in combination with clopidogrel, an antiplatelet drug, and in patients with severe renal insufficiency. We herein report an elderly patient with type 2 diabetes mellitus and severe renal insufficiency who received repaglinide and hypoglycemia three days after starting clopidogrel. The concomitant use of repaglinide and clopidogrel can lead to hypoglycemia, especially in patients with severe renal insufficiency.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemia , Insuficiência Renal , Idoso , Glicemia , Carbamatos , Clopidogrel/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Piperidinas , Insuficiência Renal/induzido quimicamente , Insuficiência Renal/complicações
7.
Diabetol Int ; 12(2): 234-240, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33786278

RESUMO

We encountered a 55-year-old Japanese man with advanced renal cell carcinoma and slowly progressive type 1 diabetes mellitus (SPT1DM), whose insulin secretory capacity was drastically reduced for a brief period after only one cycle of immune checkpoint inhibitor (ICI) treatment. The patient had been diagnosed with type 2 diabetes at the age of 53 years and was treated using oral hypoglycemic agents. However, 2 years later, he was diagnosed with SPT1DM and autoimmune thyroiditis, based on the presence of anti-glutamic acid decarboxylase antibodies (GADA) and thyroid autoantibodies, which was accompanied by advanced renal cell carcinoma. At that time, his insulin secretory capacity was preserved (CPR 2.36 ng/mL), and good glycemic control was maintained using only medical nutrition therapy (HbA1c 6.3%). He subsequently developed destructive thyroiditis approximately 2 weeks after the first cycle of ICI treatment using nivolumab (a programmed cell death-1 inhibitor) and ipilimumab (a cytotoxic T-lymphocyte-associated antigen-4 inhibitor) for advanced renal cell carcinoma. Three weeks later, his plasma glucose level markedly increased, and we detected absolute insulin deficiency and hypothyroidism. Human leukocyte antigen (HLA) analysis revealed haplotypes indicating susceptibility to type 1 diabetes mellitus (T1DM) or autoimmune thyroiditis (HLA genotype, DRB1-DQB1 *09:01-*03:03/*08:03-*06:01). He showed a good antitumor response and is currently receiving permanent insulin therapy and levothyroxine replacement with the ICI treatment. Based on this case and the available literature, patients with preexisting islet autoantibodies or SPT1DM/LADA, plus a genetic predisposition to T1DM, may have an extremely high risk of developing ICI-related T1DM for a brief period after starting ICI treatment.

8.
J Org Chem ; 84(19): 12281-12291, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483649

RESUMO

The new synthetic methodologies for perfluoroaryl-substituted (diaryl)methylphosphonates, -phosphinates via nucleophilic aromatic substitution (SNAr) were developed. Benzylphosphonate and α-fluorobenzylphosphonate reacted with a wide variety of perfluoroarenes via SNAr reaction. The reaction took place quickly and gave perfluoroarylated phosphonates in high yields. Highly diastereoselective SNAr reaction with binaphthyl-based chiral phosphinates was further carried out.

9.
Org Lett ; 21(9): 3387-3391, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31002256

RESUMO

Chiral C2-symmetric phosphinic acids were designed based on sterically demanding and helical chiral perfluoroalkyl groups at the closest α-position advancing asymmetric reaction environment and catalytic activity. The perfluoroalkyl catalysts, [(CF3)2F2] and [(C2F5)2F2] phosphinic acids, were synthesized via a stereoselective addition/cyclization sequence of methyl phosphinate and deoxofluorination. These new classes of Brønsted acid catalysts were applied to an asymmetric Friedel-Crafts reaction to give up to 89% yield and 82% R-enantioselectivity, which is higher than those obtained with the parent phosphoric acid (42% and 55.5% S).

10.
Chemistry ; 19(2): 601-5, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23180508

RESUMO

NCN-pincer Ru-complexes containing bis(oxazolinyl)phenyl ligands serve as suitable catalysts in the direct conjugate additions of α,ß-unsaturated carbonyl compounds, including ketones, esters, and amides, as well as vinylphosphonates, giving various ß-alkynyl carbonyl and phosphonate compounds. A bis(oxazolinyl)phenyl (phebox)-Ru complex also catalyzes the asymmetric conjugate addition of an alkyne with a ß-substituted, α,ß-unsaturated ketone to produce a chiral ß-alkynyl ketone.

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