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1.
FASEB J ; 35(11): e21960, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34694637

RESUMO

Soluble Klotho (sKL) is closely related to insulin resistance, which is a major factor in the progression of diabetic cardiomyopathy (DCM). The purpose of this study was to investigate the role of sKL in the regulation of DCM and the mechanism involved. A mouse model of type 2 diabetes was induced by high-fat diet and streptozotocin injection. An insulin-resistant cardiac fibroblast model was established by high glucose and high insulin. KL gene overexpression was achieved in vivo and vitro through transfection with an adenovirus-harboring KL-cDNA. Gene overexpression was used to evaluate the role of sKL in the pathophysiologic characteristics of DCM. Insulin-resistant cardiac fibroblasts reduced sKL expression and collagen deposition. Diabetic mice constructed by streptozotocin exhibited severe insulin resistance, inflammation, fibrosis, left ventricular dysfunction, and sKL downregulation. The overexpression of sKL mitigated insulin resistance and metabolic disturbance; inflammation, fibrosis, and upregulated collagen I/III content ratio in diabetic state were significantly reduced. Our findings were accompanied by notable moderation of cardiac function. Further, blunted phosphorylation of Akt was restored with sKL gene overexpression, and activated phosphorylation of extracellular signal-regulated kinase 1/2 in DCM was reduced. Our results suggest that sKL protein overexpression exerts a defensive measure by ameliorating selective insulin resistance in mouse DCM, thus revealing its underlying mechanism for potential human DCM treatment.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Glucuronidase/fisiologia , Integrina beta1/metabolismo , Miocárdio , Animais , Células Cultivadas , Fibroblastos , Fibrose , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia
2.
Nutrients ; 13(9)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34578832

RESUMO

Although fruit juices are a natural source of sugars, there is a controversy whether their sugar content has similar harmful effects as beverages' added-sugars. We aimed to study the role of fruit juice sugars in inducing overweight, hyperglycaemia, glycation and oxidative stress in normal and diabetic animal models. In diabetic Goto-Kakizaki (GK) rats, we compared the effects of four different fruit juices (4-weeks) with sugary solutions having a similar sugar profile and concentration. In vitro, the sugary solutions were more susceptible to AGE formation than fruit juices, also causing higher postprandial glycaemia and lower erythrocytes' antioxidant capacity in vivo (single intake). In GK rats, ad libitum fruit juice consumption (4-weeks) did not change body weight, glycaemia, oxidative stress nor glycation. Consumption of a matched volume of sugary solutions aggravated fasting glycaemia but had a moderate impact on caloric intake and oxidative stress/glycation markers in tissues of diabetic rats. Ad libitum availability of the same sugary solutions impaired energy balance regulation, leading to higher caloric intake than ad libitum fruit juices and controls, as well as weight gain, fasting hyperglycaemia, insulin intolerance and impaired oxidative stress/glycation markers in several tissues. We demonstrated the distinct role of sugars naturally present in fruit juices and added sugars in energy balance regulation, impairing oxidative stress, glycation and glucose metabolism in an animal model of type 2 diabetes.


Assuntos
Peso Corporal , Diabetes Mellitus Experimental/metabolismo , Açúcares da Dieta/administração & dosagem , Ingestão de Energia , Sucos de Frutas e Vegetais , Estresse Oxidativo , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/metabolismo , Sacarose na Dieta/administração & dosagem , Açúcares da Dieta/efeitos adversos , Jejum , Glucose/metabolismo , Hiperglicemia/metabolismo , Insulina/metabolismo , Masculino , Ratos , Ratos Wistar
3.
Life Sci ; 284: 119931, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34480934

RESUMO

AIMS: Retinal neovascularization is one of the visual disorders during the postmenopausal period or types two diabetes. Physical activities and also phytoestrogens with powerful antioxidant features have been widely considered to improve nervous system diseases. Therefore, this study investigated the effects of genistein, swimming exercise, and their co-treatment on retina angiogenesis, oxidative stress, and inflammation in diabetic-ovariectomized rats. MAIN METHODS: Wistar rats were randomly divided into six groups (n = 8 per group): sham, ovariectomized group (OVX), OVX + diabetes (OVX.D), OVX.D+ genistein (1 mg/kg, eight weeks; daily SC), OVX.D + exercise (eight weeks), and OVX.D+ genistein+exercise (eight weeks). At the end of 8 weeks, the retina was removed under anesthesia. The assessed effects of treatment were by measuring MiR-146a and miR-132 expression via RT-PCR, the protein levels of ERK, MMP-2, VEGF, and NF-κB via western blotting, inflammation, and oxidative stress markers levels via the Eliza. KEY FINDINGS: The results showed miR-132, miR-146b, and MMP-2, NF-κB, ERK, VEGF, TNF-α, IL-1ß proteins, and MDA factor in the OVX.D group were increased, but glutathione (GSH) was decreased in comparison with the sham and OVX groups. Both exercise and genistein treatment has reversed the disorder caused by diabetes. However, the combination of exercise and genistein was more effective than each treatment alone. SIGNIFICANCE: It can be concluded that the interaction of exercise and genistein on microRNAs and their target protein was affected in the inflammation, stress oxidative, and extracellular matrix metalloproteinase pathways, can leading to a decrease in impairment of retinal neovascularization of the ovariectomized diabetic rats.


Assuntos
Diabetes Mellitus Experimental/patologia , Genisteína/farmacologia , Inflamação/patologia , Ovariectomia , Estresse Oxidativo , Retina/patologia , Natação/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Biomarcadores/metabolismo , Diabetes Mellitus Experimental/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Genisteína/administração & dosagem , Glucose/metabolismo , Glutationa/metabolismo , Homeostase/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Malondialdeído/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos Wistar , Retina/efeitos dos fármacos
4.
Cells ; 10(9)2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34572059

RESUMO

Tumour necrosis factor alpha (TNFα) is essential in neuroinflammatory modulation. Therefore, the goal of this study is to reveal the effects of chronic hyperglycaemia and insulin treatment on TNFα expression in different gut segments and intestinal wall layers. TNFα expression was mapped by fluorescent immunohistochemistry and quantitative immunogold electron microscopy in myenteric ganglia of duodenum, ileum and colon. Tissue TNFα levels were measured by enzyme-linked immunosorbent assays in muscle/myenteric plexus-containing (MUSCLE-MP) and mucosa/submucosa/submucous plexus-containing (MUC-SUBMUC-SP) homogenates. Increasing density of TNFα-labelling gold particles is observed in myenteric ganglia from proximal to distal segments and TNFα tissue levels are much more elevated in MUSCLE-MP homogenates than in MUC-SUBMUC-SP samples in healthy controls. In the diabetics, the number of TNFα gold labels is significantly increased in the duodenum, decreased in the colon and remained unchanged in the ileal ganglia, while insulin does not prevent these diabetes-related TNFα changes. TNFα tissue concentration is also increased in MUSCLE-MP homogenates of diabetic duodenum, while decreased in MUC-SUBMUC-SP samples of diabetic ileum and colon. These findings support that type 1 diabetes has region-specific and intestinal layer-dependent effects on TNFα expression, contributing to the regional damage of myenteric neurons and their intestinal milieu.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Trato Gastrointestinal/metabolismo , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Intestinos/fisiologia , Plexo Mientérico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/etiologia , Diabetes Mellitus Experimental/patologia , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/patologia , Intestinos/efeitos dos fármacos , Masculino , Plexo Mientérico/efeitos dos fármacos , Plexo Mientérico/patologia , Ratos , Ratos Wistar
5.
PLoS One ; 16(9): e0256655, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34506507

RESUMO

Metabolic disorders are associated with a higher risk of psychiatric disorders. We previously reported that 20-week-old Otsuka Long-Evans Tokushima fatty (OLETF) rats, a model of progressive type 2 diabetes, showed increased anxiety-like behavior and regional area reductions and increased cholecystokinin-positive neurons in the corticolimbic system. However, in which stages of diabetes these alterations in OLETF rats occur remains unclear. We aimed to investigate anxiety-like behavior and its possible mechanisms at different stages of type 2 diabetes in OLETF rats. Eight- and 30-week-old OLETF rats were used as diabetic animal models at the prediabetic and progressive stages of type 2 diabetes respectively, and age-matched Long-Evans Tokushima Otsuka rats served as non-diabetic controls. In the open-field test, OLETF rats showed less locomotion in the center zone and longer latency to leave the center zone at 8 and 30 weeks old, respectively. The areas of the medial prefrontal cortex were smaller in the OLETF rats, regardless of age. The densities of cholecystokinin-positive neurons in OLETF rats were higher in the lateral and basolateral amygdala only at 8 weeks old and in the anterior cingulate and infralimbic cortices and hippocampal cornu ammonis area 3 at both ages. The densities of parvalbumin-positive neurons of OLETF rats were lower in the cornu ammonis area 2 at 8 weeks old and in the prelimbic and infralimbic cortices at both ages. No apoptotic cell death was detected in OLETF rats, but the percentage of neurons co-expressing activating transcription factor 4 and cholecystokinin and parvalbumin was higher in OLETF rats at both ages in the anterior cingulate cortex and basolateral amygdala, respectively. These results suggest that altered emotional behavior and related neurological changes in the corticolimbic system are already present in the prediabetic stage of OLETF rats.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Colecistocinina/metabolismo , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Parvalbuminas/metabolismo , Animais , Comportamento Animal , Encéfalo/metabolismo , Encéfalo/patologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/psicologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/psicologia , Masculino , Ratos , Ratos Endogâmicos OLETF
6.
Life Sci ; 284: 119905, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34453940

RESUMO

AIMS: Mitochondrial dysfunction is among the key factors for the advancement of hepatic steatosis to NAFLD and NASH. Pancreastatin (PST: human ChgA250-301) is a dysglycemic hormone, previously reported to promote steatosis and inflammation in various animal models of metabolic disorders. Recently, we observed PST deregulates energy expenditure and mitochondrial functioning in perimenopausal rats. In the current study, we aimed to decipher the role of PST instigated altered mitochondrial functioning in hepatic steatosis. MAIN METHODS: The HepG2 cells were PST exposed and the Chga gene was knocked down using siRNA and lipofectamine. Parallelly, type 2 diabetes (T2D) was developed in C57BL/6 mice by HFD feeding and administered PST inhibitor (PSTi8). KEY FINDINGS: The PST exposed cells and HFD fed mice depicted: enhanced CHGA expression detected by IF/IHC, WB, and ELISA; dysregulated cellular ROS, mitochondrial ROS, oxygen consumption rate, mitochondrial membrane potential, ATP level, and NADP/NADP ratio; enhanced apoptosis determined by MTT, TUNEL, Annexin-V FITC, and WB of Bax/bcl2 and caspase 3; hepatic lipid accumulation upon Nile Red, Oil Red O, H&E staining, and the expression of SREBP-1c, FAS, ACC, and SCD; inflammation based on expression and circulatory level of IL6, IL-1ß, and TNF-α. However, Chga knocked down HepG2 cells and PSTi8 treated mice unveiled protection from all the above abnormalities. SIGNIFICANCE: Collectively, the aforementioned data suggested the alteration in mitochondrial function induced by PST is responsible for hepatic steatosis in T2D.


Assuntos
Cromogranina A/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Fígado Gorduroso/metabolismo , Mitocôndrias Hepáticas/metabolismo , Animais , Peso Corporal , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/patologia , Dieta Hiperlipídica , Células Hep G2 , Humanos , Inflamação/metabolismo , Inflamação/patologia , Metabolismo dos Lipídeos , Masculino , Camundongos Endogâmicos C57BL
7.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445304

RESUMO

Dysfunctional islets of Langerhans are a hallmark of type 2 diabetes (T2D). We hypothesize that differences in islet gene expression alternative splicing which can contribute to altered protein function also participate in islet dysfunction. RNA sequencing (RNAseq) data from islets of obese diabetes-resistant and diabetes-susceptible mice were analyzed for alternative splicing and its putative genetic and epigenetic modulators. We focused on the expression levels of chromatin modifiers and SNPs in regulatory sequences. We identified alternative splicing events in islets of diabetes-susceptible mice amongst others in genes linked to insulin secretion, endocytosis or ubiquitin-mediated proteolysis pathways. The expression pattern of 54 histones and chromatin modifiers, which may modulate splicing, were markedly downregulated in islets of diabetic animals. Furthermore, diabetes-susceptible mice carry SNPs in RNA-binding protein motifs and in splice sites potentially responsible for alternative splicing events. They also exhibit a larger exon skipping rate, e.g., in the diabetes gene Abcc8, which might affect protein function. Expression of the neuronal splicing factor Srrm4 which mediates inclusion of microexons in mRNA transcripts was markedly lower in islets of diabetes-prone compared to diabetes-resistant mice, correlating with a preferential skipping of SRRM4 target exons. The repression of Srrm4 expression is presumably mediated via a higher expression of miR-326-3p and miR-3547-3p in islets of diabetic mice. Thus, our study suggests that an altered splicing pattern in islets of diabetes-susceptible mice may contribute to an elevated T2D risk.


Assuntos
Processamento Alternativo/fisiologia , Diabetes Mellitus Tipo 2/genética , Ilhotas Pancreáticas/metabolismo , Processamento Alternativo/genética , Animais , Diabetes Mellitus Experimental/etiologia , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Suscetibilidade a Doenças , Secreção de Insulina/genética , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Ilhotas Pancreáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/genética , Obesidade/metabolismo , Obesidade/patologia , Regulação para Cima/genética
8.
Int J Mol Sci ; 22(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34445330

RESUMO

We investigated injury-induced heat shock protein 27 (HSP27) expression and its association to axonal outgrowth after injury and different nerve repair models in healthy Wistar and diabetic Goto-Kakizaki rats. By immunohistochemistry, expression of HSP27 in sciatic nerves and DRG and axonal outgrowth (neurofilaments) in sciatic nerves were analyzed after no, immediate, and delayed (7-day delay) nerve repairs (7- or 14-day follow-up). An increased HSP27 expression in nerves and in DRG at the uninjured side was associated with diabetes. HSP27 expression in nerves and in DRG increased substantially after the nerve injuries, being higher at the site where axons and Schwann cells interacted. Regression analysis indicated a positive influence of immediate nerve repair compared to an unrepaired injury, but a shortly delayed nerve repair had no impact on axonal outgrowth. Diabetes was associated with a decreased axonal outgrowth. The increased expression of HSP27 in sciatic nerve and DRG did not influence axonal outgrowth. Injured sciatic nerves should appropriately be repaired in healthy and diabetic rats, but a short delay does not influence axonal outgrowth. HSP27 expression in sciatic nerve or DRG, despite an increase after nerve injury with or without a repair, is not associated with any alteration in axonal outgrowth.


Assuntos
Proteínas de Choque Térmico HSP27/metabolismo , Regeneração Nervosa/fisiologia , Crescimento Neuronal/fisiologia , Traumatismos dos Nervos Periféricos , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Feminino , Traumatismos dos Nervos Periféricos/metabolismo , Traumatismos dos Nervos Periféricos/fisiopatologia , Ratos , Ratos Wistar , Células de Schwann/metabolismo , Células de Schwann/fisiologia , Nervo Isquiático/metabolismo , Nervo Isquiático/fisiopatologia , Neuropatia Ciática/metabolismo , Neuropatia Ciática/fisiopatologia , Regulação para Cima
9.
Int J Mol Sci ; 22(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34445384

RESUMO

Diabetes is a predictor of nonalcoholic fatty liver disease (NAFLD). There are data suggesting that Tribulus terrestris (TT) saponins act as antidiabetic agents and protect against NAFLD. The effect of saponins may be increased by fermentable fibers such as inulin. The aim of the present study was to investigate the influence of TT saponins and TT saponins plus inulin on the plasma lipid profile and liver fatty acids of rats with induced diabetes mellitus type 2 (T2DM). The study was performed on 36 male Sprague-Dawley rats divided into two main groups: control and diabetic. Animals of the diabetic (DM) group were fed a high-fat diet and injected with streptozotocin (low doses). Animals of the control group (nDM) were on a regular diet and were injected with buffer. After the injections, the animals were split into subgroups: three non-diabetic (nDM): (i) control (c-C); (ii) saponin-treated rats (C-Sap); (iii) rats treated with saponins + inulin (C-Sap + IN), and three diabetic subgroups (DM): (iv) control (c-DM); (v) saponin-treated rats (DM-Sap); (vi) rats treated with saponins + inulin (DM-Sap + IN). Liver fatty acids were extracted and analyzed by gas chromatography, and plasma glucose and lipids were measured. The study showed significant changes in liver morphology, liver fatty acids, plasma lipid profile, and plasma glucose. In summary, supplementation with TT saponins or saponins with inulin for one month decreased the level of steatosis in rats with induced type 2 diabetes. Moreover, there were favorable effects on the plasma lipid profile in the rats. However, additional supplementation with inulin had a negative effect on liver morphology (with a microvesicular type of steatosis) in the non-diabetes group. Moreover, supplementation with inulin had a negative effect on plasma glucose in both diabetic and non-diabetic rats. These data show that a diet enriched with fermentable fibers reveals different effects in different organisms, and not all sources and forms of fiber are beneficial to health.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fígado Gorduroso/prevenção & controle , Inulina/administração & dosagem , Saponinas/administração & dosagem , Tribulus/química , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos/análise , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/metabolismo , Inulina/farmacologia , Fígado/química , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Saponinas/farmacologia , Estreptozocina , Resultado do Tratamento
10.
Chem Biol Interact ; 347: 109603, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34352274

RESUMO

AIMS: Major depressive disorder (MDD) affects approximately 322 million people worldwide and is a common comorbidity in patients with diabetes mellitus (DM). A possible pathophysiological mechanism correlating both diseases is the increased oxidative stress in brain regions due to hyperglycemia. Myrsine coriacea (Primulaceae) is popularly known as "capororoca" and studies have been shown that this plant exhibits several pharmacological properties attributed to myrsinoic acid A (MAA) and B (MAB). Indeed, previous results have been shown its effects on the central nervous system, leading us to explore possible psychotropic effects. MAIN METHODS: The effects of treatment with hydroalcoholic extract of the barks from Myrsine coriacea (HEBMC, 150 mg/kg, o.g.), MAA (5 mg/kg, o.g.), and MAB (3 mg/kg, o.g.) were evaluated in streptozotocin (75 mg/kg, i.p.)-induced diabetic female rats. After 28 days of treatments, rats were submitted to the forced swim test (FST) and open field test (OFT). Also, superoxide dismutase (SOD) and catalase (CAT) activities, reduced glutathione (GSH) and lipid hydroperoxides (LOOH) levels were evaluated in the hippocampus (HIP) and prefrontal cortex (PFC) of these rats. KEY FINDINGS: The treatment with MAA or MAB increased the latency of first immobility in diabetic rats, and the HEBMC administration decreased the immobility time, and increase the climbing in FST. However, only MAB treatment reduces the immobility time, increases the climbing, and swimming in FST, and increases the crossing of diabetic animals in the OFT. Besides, this behavioral improvement promoted by MAB administration was accompanied by reducing in oxidative stress in the HIP and PFC, but not reducing hyperglycemia in diabetic rats. SIGNIFICANCE: The results suggest that MAB's antioxidant effect in the HIP of diabetic animals may be essential to its antidepressant-like effect.


Assuntos
Alcenos/uso terapêutico , Antidepressivos/uso terapêutico , Benzofuranos/uso terapêutico , Depressão/prevenção & controle , Hipocampo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Animais , Catalase/metabolismo , Depressão/etiologia , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Feminino , Myrsine/química , Teste de Campo Aberto/efeitos dos fármacos , Casca de Planta/química , Extratos Vegetais/uso terapêutico , Caules de Planta/química , Ratos Wistar , Estreptozocina
11.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361788

RESUMO

This research investigated a UPLC-QTOF/ESI-MS-based phytochemical profiling of Combretum indicum leaf extract (CILEx), and explored its in vitro antioxidant and in vivo antidiabetic effects in a Long-Evans rat model. After a one-week intervention, the animals' blood glucose, lipid profile, and pancreatic architectures were evaluated. UPLC-QTOF/ESI-MS fragmentation of CILEx and its eight docking-guided compounds were further dissected to evaluate their roles using bioinformatics-based network pharmacological tools. Results showed a very promising antioxidative effect of CILEx. Both doses of CILEx were found to significantly (p < 0.05) reduce blood glucose, low-density lipoprotein (LDL), and total cholesterol (TC), and increase high-density lipoprotein (HDL). Pancreatic tissue architectures were much improved compared to the diabetic control group. A computational approach revealed that schizonepetoside E, melianol, leucodelphinidin, and arbutin were highly suitable for further therapeutic assessment. Arbutin, in a Gene Ontology and PPI network study, evolved as the most prospective constituent for 203 target proteins of 48 KEGG pathways regulating immune modulation and insulin secretion to control diabetes. The fragmentation mechanisms of the compounds are consistent with the obtained effects for CILEx. Results show that the natural compounds from CILEx could exert potential antidiabetic effects through in vivo and computational study.


Assuntos
Antioxidantes/farmacologia , Combretum/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Arbutina/química , Arbutina/isolamento & purificação , Sítios de Ligação , Glicemia/efeitos dos fármacos , HDL-Colesterol/agonistas , HDL-Colesterol/sangue , LDL-Colesterol/antagonistas & inibidores , LDL-Colesterol/sangue , Biologia Computacional/métodos , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Flavonoides/química , Flavonoides/isolamento & purificação , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Insulina/agonistas , Insulina/metabolismo , Masculino , Modelos Moleculares , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Extratos Vegetais/química , Folhas de Planta/química , Ligação Proteica , Conformação Proteica , Ratos , Ratos Long-Evans , Triterpenos/química , Triterpenos/isolamento & purificação
12.
Chem Biol Interact ; 347: 109617, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34391751

RESUMO

PURPOSE: This study was designed to investigate the mechanism of Dapagliflozin (Dapa) cardioprotection against diabetic cardiomyopathy (DCM). Structural and functional changes in the heart as well as decrease of erythropoietin (EPO) levels were reported in DCM. EPO simultaneously activates three pathways: the Janus-activated kinase-signal transducer and activator of transcription (JAK2/STAT5), phosphatidylinositol-3-kinase-Akt (PI3K/Akt), and extracellular signal-related kinase (ERK/MAPK) cascades, that result in proliferation and differentiation of cardiac cells. METHODS AND RESULTS: DCM was induced by a high fat diet for 10 weeks followed by administration of streptozotocin. After confirmation of diabetes, rats were divided randomly to 5 groups: Group 1; normal control group, Group 2; untreated diabetic group and Groups (3-5); diabetic groups received Dapa daily (0.75 mg, 1.5 or 3 mg/Kg, p.o) respectively for a month. At the end of the experiment, full anaesthesia was induced in all rats using ether inhalation and ECG was recorded. Blood samples were collected then rats were sacrificed and their heart were dissected out and processed for biochemical and histopathological studies. Untreated diabetic rats showed abnormal ECG pattern, elevation of serum cardiac enzymes, decrease EPO levels, downregulation of P-Akt, P-JAK2 and pMAPK pathways, abnormal histological structure of the heart and increase immunostaining intensity of P53 and TNF α in the cardiomyocytes. Dapa in a dose dependent manner attenuated the alterations in the previously mentioned parameters. CONCLUSION: The cardioprotective effect of Dapa could be mediated by increasing EPO levels and activation of P-Akt, P-JAK2 and pMAPK signalling cascades which in turn decrease apoptosis.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Cardiotônicos/uso terapêutico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Glucosídeos/uso terapêutico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/complicações , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/patologia , Eletrocardiografia/efeitos dos fármacos , Eritropoetina/sangue , Eritropoetina/metabolismo , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Ratos Wistar , Estreptozocina
13.
Invest Ophthalmol Vis Sci ; 62(10): 31, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34431974

RESUMO

Purpose: To analyze the gut bacterial microbiome of streptozotocin-induced diabetic rats and rats with retinal changes. Methods: Induction of diabetes was confirmed by an increase in blood sugar (>150 mg/dL), and the progression of diabetes with retinal changes was assessed by histology and immunohistochemistry of retinal sections. Microbiomes were generated using fecal DNA, and the V3-V4 amplicons were sequenced and analyzed by QIIME and R. Results: Dysbiosis in the gut microbiome of diabetic rats and diabetic rats with retinal changes was observed at the phylum and genus levels compared with the control rats. Heat-map analysis based on the differentially abundant genera indicated that the microbiomes of controls and diabetic rats separated into two distinct clusters. The majority of the microbiomes in diabetic rats with retinal changes also formed a distinct cluster from the control rats. ß-diversity analysis separated the microbiome of control rats from the microbiome of diabetic rats and diabetic rats with retinal changes, but the microbiomes of diabetic rats and diabetic rats with retinal changes showed an overlap. Functional analysis indicated that the enhanced inflammation in diabetic rats showing retinal changes could be ascribed to a decrease in anti-inflammatory bacteria and an increase in pathogenic and proinflammatory bacteria. Conclusions: This study showed that the gut bacterial microbiome in diabetic rats with retinal changes was different compared with control rats. The results could help develop novel therapeutics for diabetics and diabetic individuals with retinal changes.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Disbiose/microbiologia , Microbioma Gastrointestinal/fisiologia , Animais , Diabetes Mellitus Experimental/complicações , Disbiose/etiologia , Disbiose/metabolismo , Fezes/microbiologia , Seguimentos , Ratos
14.
Biomolecules ; 11(7)2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34356612

RESUMO

Vascular endothelial growth factor (VEGF) is a major therapeutic target for blood-retina barrier (BRB) breakdown in diabetic retinopathy (DR), age-related macular degeneration (AMD), and other hypoxic retinal vascular disorders. To determine whether VEGF is a direct regulator of retinal neuronal function and its potential role in altering vision during the progression of DR, we examined the immediate impact of recombinant VEGF (rVEGF) on photoreceptor function with electroretinography in C57BL6 background wild-type (WT) and Akita spontaneous diabetic mice. Shortly after intravitreal injections, rVEGF caused a significant reduction of scotopic ERG a-wave and b-wave amplitudes and photopic ERG b-wave amplitudes in a dose-dependent manner in dark-adapted 1.5-mo-old WT mice. Compared with WT controls, 5-mo-old Akita spontaneous diabetic mice demonstrated a significant reduction in scotopic ERG a-wave and b-wave amplitudes and photopic ERG b-wave amplitudes. However, the effect of rVEGF altered photoreceptor function in WT controls was diminished in 5-mo-old Akita spontaneous diabetic mice. In conclusion, our results suggest that VEGF is a direct functional regulator of photoreceptors and VEGF up-regulation in DR is a contributing factor to diabetes-induced alteration of photoreceptor function. This information is critical to the understanding of the therapeutic effect and to the care of anti-VEGF drug-treated patients for BRB breakdown in DR, AMD, and other hypoxic retinal vascular disorders.


Assuntos
Barreira Hematorretiniana/metabolismo , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Barreira Hematorretiniana/patologia , Diabetes Mellitus Experimental/patologia , Retinopatia Diabética/patologia , Camundongos , Células Fotorreceptoras de Vertebrados/patologia , Fator A de Crescimento do Endotélio Vascular/farmacologia
15.
Am J Physiol Endocrinol Metab ; 321(3): E392-E409, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34370593

RESUMO

The improvement of cognitive function following bariatric surgery has been highlighted, yet its underlying mechanisms remain elusive. Finding the improved brain glucose uptake of patients after Roux-en-Y gastric bypass (RYGB), duodenum-jejunum bypass (DJB), and sham surgery (Sham) were performed on obese and diabetic Wistar rats, and intracerebroventricular (ICV) injection of glucagon-like peptide-1 (GLP-1) analog liraglutide (Lira), antagonist exendin-(9-39) (Exe-9), and the viral-mediated GLP-1 receptor (Glp-1r) knockdown (KD) were applied on both groups to elucidate the role of GLP-1 in mediating cognitive function and brain glucose uptake assessed with the Morris water maze (MWM) and positron emission tomography (PET). Insulin and GLP-1 in serum and cerebral spinal fluid (CSF) were measured, and the expression of glucose uptake-related proteins including glucose transporter 1 (GLUT-1), GLUT-4, phospho-Akt substrate of 160kDa (pAS160), AS160, Rab10, Myosin-Va as well as the c-fos marker in the brain were examined. Along with augmented glucose homeostasis following DJB, central GLP-1 was correlated with the improved cognitive function and ameliorated brain glucose uptake, which was further confirmed by the enhancive role of Lira on both groups whereas the Exe-9 and Glp-1r KD were opposite. Known to activate insulin-signaling pathways, central GLP-1 contributes to improved cognitive function and brain glucose uptake after DJB.NEW & NOTEWORTHY The improvement of cognitive function following bariatric surgery has been highlighted while its mechanisms remain elusive. The brain glucose uptake of patients was improved after RYGB, and the DJB and sham surgery performed on obese and diabetic Wistar rats revealed that the elevated central GLP-1 contributes to the dramatic improvement of cognitive function, brain glucose uptake, transport, glucose sensing, and neuronal activation.


Assuntos
Cognição , Diabetes Mellitus Experimental/metabolismo , Derivação Gástrica , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Obesidade/metabolismo , Animais , Encéfalo/metabolismo , Duodeno/cirurgia , Glucose , Jejuno/cirurgia , Obesidade/cirurgia , Ratos Wistar
16.
Int J Mol Sci ; 22(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34445075

RESUMO

Pre-weaned porcine islets (PPIs) represent an unlimited source for islet transplantation but are functionally immature. We previously showed that necrostatin-1 (Nec-1) immediately after islet isolation enhanced the in vitro development of PPIs. Here, we examined the impact of Nec-1 on the in vivo function of PPIs after transplantation in diabetic mice. PPIs were isolated from pancreata of 8-15-day-old, pre-weaned pigs and cultured in media alone, or supplemented with Nec-1 (100 µM) on day 0 or on day 3 of culture (n = 5 for each group). On day 7, islet recovery, viability, oxygen consumption rate, insulin content, cellular composition, insulin secretion capacity, and transplant outcomes were evaluated. While islet viability and oxygen consumption rate remained high throughout 7-day tissue culture, Nec-1 supplementation on day 3 significantly improved islet recovery, insulin content, endocrine composition, GLUT2 expression, differentiation potential, proliferation capacity of endocrine cells, and insulin secretion. Adding Nec-1 on day 3 of tissue culture enhanced the islet recovery, proportion of delta cells, beta-cell differentiation and proliferation, and stimulation index. In vivo, this leads to shorter times to normoglycemia, better glycemic control, and higher circulating insulin. Our findings identify the novel time-dependent effects of Nec-1 supplementation on porcine islet quantity and quality prior to transplantation.


Assuntos
Diabetes Mellitus Experimental/terapia , Imidazóis/farmacologia , Indóis/farmacologia , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/efeitos dos fármacos , Técnicas de Cultura de Tecidos/métodos , Animais , Diabetes Mellitus Experimental/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/fisiologia , Camundongos Nus , Suínos , Transplante Heterólogo/métodos , Transplantes/efeitos dos fármacos , Transplantes/fisiologia
17.
Biomed Res Int ; 2021: 9920826, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34341763

RESUMO

Background: Abrus precatorius is used in folk medicine across Afro-Asian regions of the world. Earlier, glucose lowering and pancreato-protective effects of Abrus precatorius leaf extract (APLE) was confirmed experimentally in STZ/nicotinamide-induced diabetic rats; however, the underlying mechanism of antidiabetic effect and pancreato-protection remained unknown. Objective: This study elucidated antidiabetic mechanisms and pancreato-protective effects of APLE in diabetic rats. Materials and Methods: APLE was prepared by ethanol/Soxhlet extraction method. Total phenols and flavonoids were quantified calorimetrically after initial phytochemical screening. Diabetes mellitus (DM) was established in adult Sprague-Dawley rats (weighing 120-180 g) of both sexes by daily sequential injection of nicotinamide (48 mg/kg; ip) and Alloxan (120 mg/kg; ip) over a period of 7 days. Except control rats which had fasting blood glucose (FBG) of 4.60 mmol/L, rats having stable FBG (16-21 mmol/L) 7 days post-nicotinamide/Alloxan injection were considered diabetic and were randomly reassigned to one of the following groups (model, APLE (100, 200, and 400 mg/kg, respectively; po) and metformin (300 mg/kg; po)) and treated daily for 18 days. Bodyweight and FBG were measured every 72 hours for 18 days. On day 18, rats were sacrificed under deep anesthesia; organs (kidney, liver, pancreas, and spleen) were isolated and weighed. Blood was collected for estimation of serum insulin, glucagon, and GLP-1 using a rat-specific ELISA kit. The pancreas was processed, sectioned, and H&E-stained for histological examination. Effect of APLE on enzymatic activity of alpha (α)-amylase and α-glucosidase was assessed. Antioxidant and free radical scavenging properties of APLE were assessed using standard methods. Results: APLE dose-dependently decreased the initial FBG by 68.67%, 31.07%, and 4.39% compared to model (4.34%) and metformin (43.63%). APLE (100 mg/kg) treatment restored weight loss relative to model. APLE increased serum insulin and GLP-1 but decreased serum glucagon relative to model. APLE increased both the number and median crosssectional area (×106 µm2) of pancreatic islets compared to that of model. APLE produced concentration-dependent inhibition of α-amylase and α-glucosidase relative to acarbose. APLE concentration dependently scavenged DPPH and nitric oxide (NO) radicals and demonstrated increased ferric reducing antioxidant capacity (FRAC) relative to standards. Conclusion: Antidiabetic effect of APLE is mediated through modulation of insulin and GLP-1 inversely with glucagon, noncompetitive inhibition of α-amylase and α-glucosidase, free radical scavenging, and recovery of damaged/necro-apoptosized pancreatic ß-cells.


Assuntos
Abrus/química , Diabetes Mellitus Experimental/metabolismo , Peptídeo 1 Semelhante ao Glucagon/sangue , Glucagon/sangue , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo , Aloxano , Animais , Antioxidantes/metabolismo , Compostos de Bifenilo/química , Glicemia/metabolismo , Peso Corporal , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Feminino , Flavonoides/análise , Sequestradores de Radicais Livres/farmacologia , Cobaias , Concentração Inibidora 50 , Insulina/sangue , Ferro/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/patologia , Cinética , Masculino , Niacinamida , Fenóis/análise , Compostos Fitoquímicos/análise , Picratos/química , Extratos Vegetais/farmacologia , Ratos Sprague-Dawley
18.
Arch Biochem Biophys ; 710: 109000, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343486

RESUMO

Impaired endothelium-mediated vasodilation and/or increased sensitivity to vasoconstrictors lead to vascular smooth muscle cell (VSMC) dysfunction in individuals with diabetes. Diabetic nephropathy is associated with a considerably higher risk of cardiovascular disease and death than their nondiabetic counterparts. We studied the activity of Cullin 3 RING ubiquitin ligase (CRL3) and its substrates in mice using an intraperitoneal injection of streptozotocin (STZ) and db/db mice. The levels of CRL3 adaptors, including Kelch-like 2/3 (KLHL2/3) and Rho-related BTB domain-containing protein 1, were significantly decreased in the aortic tissues and heart of the STZ group, whereas the levels of Cullin 3 (CUL3) and its neddylated derivatives were substantially increased. Decreased KLHL3 expression and significantly increased expression of NEDD8 conjugates were observed in the kidneys of db/db mice. The neddylation inhibitor MLN4924 decreased the degradation of KLHL2/KLHL3 under high-glucose conditions with/without insulin, and transfection with KLHL2 promoted the degradation of its substrates with-no-lysine (WNK) kinases. Increased abundance of WNK3, RhoA/ROCK activity and phosphodiesterase 5 enhanced the sensibility to vasoconstrictors and impaired vasodilation. Moreover, WNK3 localized in VSMCs undergoing cell division, and high-glucose medium increased WNK3 signaling in VSMCs undergoing mitosis, which might explain the increased thickness of aortic tissues in subjects with diabetes. Increases in WNK4 abundance resulted in increased sodium reabsorption in the distal renal tubules. Thus, KLHL2/RhoBTB1/KLHL3 inactivation in the aortic tissues and kidney is a result of excessive activation of neddylation in hyperglycemia and hyperinsulinemia, which affects vascular tone and sodium reabsorption.


Assuntos
Proteínas Culina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Sódio/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Vasoconstrição/fisiologia , Animais , Aorta/metabolismo , Aorta/patologia , Células Cultivadas , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/fisiopatologia , Humanos , Rim/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Proteínas dos Microfilamentos/antagonistas & inibidores , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
19.
Life Sci ; 283: 119870, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352258

RESUMO

OBJECTIVE: Increased renal and hepatic gluconeogenesis are important sources of fasting hyperglycemia in type 2 diabetes (T2D). The inhibitory effect of co-administration of sodium nitrite and sodium hydrosulfide (NaSH) on hepatic but not renal gluconeogenesis has been reported in rats with T2D. The present study aimed to determine the effects of co-administration of sodium nitrite and NaSH on the expression of genes involved in renal gluconeogenesis in rats with T2D. METHODS: T2D was induced by a combination of a high-fat diet and low-dose streptozotocin (30 mg/kg). Male Wistar rats were divided into 5 groups (n = 6/group): Control, T2D, T2D + nitrite, T2D + NaSH, and T2D + nitrite+NaSH. Nitrite and NaSH were administered for nine weeks at a dose of 50 mg/L (in drinking water) and 0.28 mg/kg (daily intraperitoneal injection), respectively. Serum levels of urea and creatinine, and mRNA expressions of PEPCK, G6Pase, FBPase, PC, PI3K, AKT, PGC-1α, and FoxO1 in the renal tissue, were measured at the end of the study. RESULTS: Nitrite decreased mRNA expression of PEPCK by 39%, G6Pase by 43%, FBPase by 41%, PC by 63%, PGC-1α by 45%, and FoxO1 by 27% in the renal tissue of rats with T2D; co-administration of nitrite and NaSH further decreases FoxO1, while had no additive effects on the tissue expression of the other genes. In addition, nitrite+NaSH decreased elevated serum urea levels by 58% and creatinine by 37% in rats with T2D. CONCLUSION: The inhibitory effect of nitrite on gluconeogenesis in T2D rats is at least in part due to decreased mRNA expressions of renal gluconeogenic genes. Unlike effects on hepatic gluconeogenesis, co-administration of nitrite and NaSH has no additive effects on genes involved in renal gluconeogenesis in rats with T2D.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Gluconeogênese/efeitos dos fármacos , Rim/metabolismo , Nitrito de Sódio/farmacologia , Sulfetos/farmacologia , Animais , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/patologia , Rim/patologia , Masculino , Ratos , Ratos Wistar
20.
Nutrients ; 13(8)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34444782

RESUMO

Substrates of semicarbazide-sensitive amine oxidase (SSAO) exert insulin-like actions in adipocytes. One of them, benzylamine (Bza) exhibits antihyperglycemic properties in several rodent models of diabetes. To further study the antidiabetic potential of this naturally occurring amine, a model of severe type 2 diabetes, the obese db-/- mouse, was subjected to oral Bza administration. To this end, db-/- mice and their lean littermates were treated at 4 weeks of age by adding 0.5% Bza in drinking water for seven weeks. Body mass, fat content, blood glucose and urinary glucose output were followed while adipocyte insulin responsiveness and gene expression were checked at the end of supplementation, together with aorta nitrites. Bza supplementation delayed the appearance of hyperglycemia, abolished polydypsia and glycosuria in obese/diabetic mice without any detectable effect in lean control, except for a reduction in food intake observed in both genotypes. The improvement of glucose homeostasis was observed in db-/- mice at the expense of increased fat deposition, especially in the subcutaneous white adipose tissue (SCWAT), without sign of worsened inflammation or insulin responsiveness and with lowered circulating triglycerides and uric acid, while NO bioavailability was increased in aorta. The higher capacity of SSAO in oxidizing Bza in SCWAT, found in the obese mice, was unaltered by Bza supplementation and likely involved in the activation of glucose utilization by adipocytes. We propose that Bza oxidation in tissues, which produces hydrogen peroxide mainly in SCWAT, facilitates insulin-independent glucose utilization. Bza could be considered as a potential agent for dietary supplementation aiming at preventing diabetic complications.


Assuntos
Benzilaminas/administração & dosagem , Benzilaminas/metabolismo , Complicações do Diabetes/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Suplementos Nutricionais , Obesidade/metabolismo , Adipócitos/metabolismo , Amina Oxidase (contendo Cobre)/metabolismo , Animais , Benzilaminas/farmacologia , Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Ingestão de Alimentos , Glucose/metabolismo , Humanos , Peróxido de Hidrogênio , Hiperglicemia/metabolismo , Hipoglicemiantes/metabolismo , Insulina/sangue , Masculino , Camundongos , Camundongos Knockout , Camundongos Obesos , Compostos Fitoquímicos , Receptores para Leptina/genética
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