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1.
FEBS Lett ; 2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39095330

RÉSUMÉ

Goto-Kakizaki (GK) rats develop a well-defined insulin resistance (IR) and type 2 diabetes mellitus (T2DM) without presenting obesity. The lymphocyte profile in nonobese diabetic conditions is not yet characterized. Therefore, GK rats were chosen to explore T lymphocyte (TL) dynamics at various stages (21, 60, and 120 days) compared to Wistar rats. GK rats exhibit progressive disruption of glucose regulation, with early glucose intolerance at 21 days and reduced insulin sensitivity at 60 days, confirming IR. Glucose transporter 1 (GLUT1) expression was consistently elevated in GK rats, suggesting heightened TL activation. T-regulatory lymphocyte markers diminished at 21 days. However, GK rats showed increased Th1 markers and reduced Gata-3 expression (crucial for Th2 cell differentiation) at 120 days. These findings underscore an early breakdown of anti-inflammatory mechanisms in GK rats, indicating a proinflammatory TL profile that may worsen chronic inflammation in T2DM.

2.
Metab Syndr Relat Disord ; 22(7): 494-498, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39037911

RÉSUMÉ

Liver diseases have a global prevalence of 25%, accounting for 4% of all deaths worldwide, and are associated with a 36% increased risk of fatal and nonfatal cardiovascular events. Metabolic dysfunction-associated steatotic liver disease constitutes the liver expression of metabolic syndrome and represents the primary type of liver disease. Microscopical analysis of biopsies, which allows the evaluation of a small portion of tissue with inferences made to the entire organ, is considered the gold standard for determining the presence of liver diseases. However, potential sampling errors in liver biopsies are conceivable because the obtained tissue represents only a tiny fraction of the entire liver mass and may not accurately reflect the true pathological state. Studies have demonstrated the existence of sampling errors in liver biopsies, particularly concerning the severity of inflammation, degree of fibrosis, and the presence of cirrhosis. Also, clinical studies have shown that histopathological abnormalities are better detected in humans when liver samples are collected from both the right and the left lobes. However, a gap exists in clinical investigation to clarify the role of differences between these lobes in improving the diagnostic and prognostic for liver diseases. Building upon the heterogeneous nature of pathological alterations observed in liver lobes, this perspective review provided recommendations to enhance the precision of diagnosis and prognostic accuracy of liver diseases.


Sujet(s)
Maladies du foie , Foie , Humains , Foie/anatomopathologie , Maladies du foie/anatomopathologie , Maladies du foie/diagnostic , Maladies du foie/épidémiologie , Biopsie , Pronostic , Syndrome métabolique X/anatomopathologie , Syndrome métabolique X/épidémiologie , Syndrome métabolique X/diagnostic , Cirrhose du foie/anatomopathologie , Cirrhose du foie/diagnostic , Cirrhose du foie/épidémiologie , Animaux
3.
Int J Sports Med ; 2024 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-38986487

RÉSUMÉ

It is well known that cardiometabolic dysfunction gradually increases after menopause, and the sedentary lifestyle can aggravate this condition. Therefore, we compared the effects of aerobic exercise training during the premenopausal period and after ovariectomy (OVX) on metabolic, hemodynamic, and autonomic parameters in an experimental rat model of menopause. The female rats were divided into four groups: control (C), sedentary OVX (SO), trained OVX (TO), and previously trained OVX (PTO). The PTO group was trained for 4 weeks prior to+8 weeks after OVX, and the TO group trained only after OVX on a motor treadmill. Autonomic modulation was evaluated, white adipose tissue (WAT) was removed and weighed, and lipolysis was assessed. The citrate synthase activity in the soleus muscle was analyzed. The trained groups prevented the impairment of baroreceptor reflex sensitivity in relation to SO; however, only PTO reduced the low-frequency band of the pulse interval compared to SO. PTO reduced the weight of WAT compared to the other groups; lipolysis in PTO was similar to that in C. PTO preserved muscle metabolic injury in all types of fibers analyzed. In conclusion, this study suggests that exercise training should be recommended in a premenopausal model to prevent cardiometabolic and autonomic menopause-induced deleterious effects.

4.
Int J Mol Sci ; 25(12)2024 Jun 18.
Article de Anglais | MEDLINE | ID: mdl-38928418

RÉSUMÉ

Breast cancer is the type of cancer with the highest prevalence in women worldwide. Skeletal muscle atrophy is an important prognostic factor in women diagnosed with breast cancer. This atrophy stems from disrupted skeletal muscle homeostasis, triggered by diminished anabolic signalling and heightened inflammatory conditions, culminating in an upregulation of skeletal muscle proteolysis gene expression. The importance of delving into research on modulators of skeletal muscle atrophy, such as microRNAs (miRNAs), which play a crucial role in regulating cellular signalling pathways involved in skeletal muscle protein synthesis and degradation, has been recognised. This holds true for conditions of homeostasis as well as pathologies like cancer. However, the determination of specific miRNAs that modulate skeletal muscle atrophy in breast cancer conditions has not yet been explored. In this narrative review, we aim to identify miRNAs that could directly or indirectly influence skeletal muscle atrophy in breast cancer models to gain an updated perspective on potential therapeutic targets that could be modulated through resistance exercise training, aiming to mitigate the loss of skeletal muscle mass in breast cancer patients.


Sujet(s)
Tumeurs du sein , microARN , Muscles squelettiques , Amyotrophie , Humains , microARN/génétique , microARN/métabolisme , Tumeurs du sein/génétique , Tumeurs du sein/anatomopathologie , Tumeurs du sein/métabolisme , Femelle , Amyotrophie/métabolisme , Amyotrophie/génétique , Amyotrophie/anatomopathologie , Amyotrophie/étiologie , Muscles squelettiques/métabolisme , Muscles squelettiques/anatomopathologie , Animaux , Développement musculaire/génétique
5.
High Blood Press Cardiovasc Prev ; 31(3): 321-327, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38735994

RÉSUMÉ

INTRODUCTION: Cardiac autonomic system functioning may be altered by obesity leading to cardiovascular diseases and associated complications. Military police officers are exposed to traditional and occupational risk factors for the development of CVD, however data on the cardiovascular health in this population is still scarce. AIM: In this cross-sectional study, we investigated the impact of obesity on cardiac autonomic modulation and the hemodynamic profile in male active-duty military police officers. METHODS: The body composition of the volunteers was assessed by octapolar electrical bioimpedance. Participants were classified as non-obese or obese in accordance with their body fat, with further subgroups as physically active obese or insufficiently active obese using International Physical Activity Questionnaire (IPAQ). Cardiac autonomic modulation was assessed by heart rate variability and the automatic oscillometric method allowed us to assess hemodynamic features. RESULTS: 102 military police officers from the state of São Paulo participated in the study. Cardiac autonomic modulation revealed significant impairment in time and frequency domains and non-linear methods in the obese group compared to the non-obese (p < 0.05). A higher physical activity level did not alter these results in the obese group. However, no significant differences in the hemodynamic profile were observed between groups (p > 0.05). CONCLUSION: These findings suggest a negative association between obesity and cardiac autonomic modulation in military police officers, unaffected by increased physical activity.


Sujet(s)
Système nerveux autonome , Rythme cardiaque , Obésité , Police , Humains , Mâle , Études transversales , Système nerveux autonome/physiopathologie , Adulte , Obésité/physiopathologie , Obésité/diagnostic , Obésité/épidémiologie , Brésil/épidémiologie , Coeur/innervation , Coeur/physiopathologie , Santé au travail , Hémodynamique , Santé militaire , Adiposité , Appréciation des risques , Personnel militaire , Jeune adulte
6.
Br J Nutr ; : 1-11, 2024 May 27.
Article de Anglais | MEDLINE | ID: mdl-38800991

RÉSUMÉ

Ganoderma lucidum (a mushroom used in traditional Chinese medicine) compounds may attenuate ageing-related physiological changes and restore normal immunity. However, studies on the physiological effects of Ganoderma lucidum dry extract food supplements are few. Therefore, here, we aimed to investigate the effects of Ganoderma lucidum dry extract food supplement on the lymphocyte function of older women. This was a double-blind clinical trial (n 60) with a final 39 older volunteers, divided into two groups Ganoderma lucidum (n 23) and placebo (n 16). The Ganoderma lucidum group received 2000 mg/d of Ganoderma lucidum dry extract for 8 weeks. We used flow cytometry to determine the lymphocyte profile. CD4+ lymphocyte gene expression was evaluated by real-time polymerase chain reaction. We observed that in the Ganoderma lucidum group, concanavalin A stimulation increased lymphocyte proliferation. Further, we observed an increase in expression of Forkhead box P3, transforming growth factor-beta, IL-10, IL-6, retinoic acid receptor-related orphan receptor gamma, GATA-binding protein 3 and interferon gamma genes in the Ganoderma lucidum group. Furthermore, in the Ganoderma lucidum group, ionomycin and phorbol 12-myristate 13-acetate stimulation led to decrease in Th17+ cells and increase in Th2+ cells. Thus, in older women, Ganoderma lucidum regulates T lymphocyte function leading to a predominant anti-inflammatory action but does not induce T lymphocyte proliferation through CD28 signalling pathway.

7.
Br J Nutr, 1 - 11, mai. 2024
Article de Anglais | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5451

RÉSUMÉ

Ganoderma lucidum (a mushroom used in traditional Chinese medicine) compounds may attenuate ageing-related physiological changes and restore normal immunity. However, studies on the physiological effects of Ganoderma lucidum dry extract food supplements are few. Therefore, here, we aimed to investigate the effects of Ganoderma lucidum dry extract food supplement on the lymphocyte function of older women. This was a double-blind clinical trial (n 60) with a final 39 older volunteers, divided into two groups Ganoderma lucidum (n 23) and placebo (n 16). The Ganoderma lucidum group received 2000 mg/d of Ganoderma lucidum dry extract for 8 weeks. We used flow cytometry to determine the lymphocyte profile. CD4+ lymphocyte gene expression was evaluated by real-time polymerase chain reaction. We observed that in the Ganoderma lucidum group, concanavalin A stimulation increased lymphocyte proliferation. Further, we observed an increase in expression of Forkhead box P3, transforming growth factor-beta, IL-10, IL-6, retinoic acid receptor-related orphan receptor gamma, GATA-binding protein 3 and interferon gamma genes in the Ganoderma lucidum group. Furthermore, in the Ganoderma lucidum group, ionomycin and phorbol 12-myristate 13-acetate stimulation led to decrease in Th17+ cells and increase in Th2+ cells. Thus, in older women, Ganoderma lucidum regulates T lymphocyte function leading to a predominant anti-inflammatory action but does not induce T lymphocyte proliferation through CD28 signalling pathway.

8.
FEBS Lett, 1-15, jun. 2024
Article de Anglais | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5445

RÉSUMÉ

Goto-Kakizaki (GK) rats develop a well-defined insulin resistance (IR) andtype 2 diabetes mellitus (T2DM) without presenting obesity. The lymphocyteprofile in nonobese diabetic conditions is not yet characterized. Therefore,GK rats were chosen to explore T lymphocyte (TL) dynamics at variousstages (21, 60, and 120 days) compared to Wistar rats. GK rats exhibit progressive disruption of glucose regulation, with early glucose intolerance at21 days and reduced insulin sensitivity at 60 days, confirming IR. Glucosetransporter 1 (GLUT1) expression was consistently elevated in GK rats, sug-gesting heightened TL activation. T-regulatory lymphocyte markers dimin-ished at 21 days. However, GK rats showed increased Th1 markers andreduced Gata-3 expression (crucial for Th2 cell differentiation) at 120 days.These findings underscore an early breakdown of anti-inflammatory mecha-nisms in GK rats, indicating a proinflammatory TL profile that may worsenchronic inflammation in T2DM.

9.
Braz J Med Biol Res, v. 57, n. 2024, e13468, abril 2024
Article de Anglais | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5400

RÉSUMÉ

In this double-blind placebo-controlled randomized investigation, we assessed the tolerability of glutamine in older adults recruited from three daycare centers. The relevance of studying glutamine supplementation in elderly patients lies in its potential to provide a well-tolerated intervention. Glutamine, a crucial amino acid, plays a vital role in various physiological processes, including immune function and protein synthesis. Understanding its impact on older adults is essential, given the potential implications for their health and well-being. Participants received a daily dose of 12.4 g of oral effervescent glutamine (EGln group) or maltodextrin (placebo group) for 60 days. Fifteen patients from each group completed the study. The mean ages were 77.0±9.1 and 79.0±6.9 years for the EGln and placebo groups, respectively. We evaluated body mass index, aminogram, hemogram, plasma levels of glucose, prealbumin, albumin, urea, creatinine, uric acid, C-reactive protein, vitamin D, calcium, sodium, potassium, and the plasma activities of aspartate aminotransferase and alanine aminotransferase. Notably, we quantified a broad array of inflammatory markers and growth factors providing a holistic understanding of the potential effects of glutamine supplementation. The results demonstrated that oral glutamine did not induce significant changes in any evaluated parameters, and no adverse effects were reported. This finding suggested that the dosage of glutamine used in this study was well-tolerated and safe. This information contributes to the broader understanding of glutamine supplementation, emphasizing its safety and supporting its potential as a viable intervention for maintaining health in aging individuals.

11.
Nutrients ; 15(22)2023 Nov 07.
Article de Anglais | MEDLINE | ID: mdl-38004105

RÉSUMÉ

AIM: To evaluate the effects of resistance exercise training (RET) and/or glutamine supplementation (GS) on signaling protein synthesis in adult rat skeletal muscles. METHODS: The following groups were studied: (1) control, no exercise (C); (2) exercise, hypertrophy resistance exercise training protocol (T); (3) no exercise, supplemented with glutamine (G); and (4) exercise and supplemented with glutamine (GT). The rats performed hypertrophic training, climbing a vertical ladder with a height of 1.1 m at an 80° incline relative to the horizontal with extra weights tied to their tails. The RET was performed three days a week for five weeks. Each training session consisted of six ladder climbs. The extra weight load was progressively increased for each animal during each training session. The G groups received daily L-glutamine by gavage (one g per kilogram of body weight per day) for five weeks. The C group received the same volume of water during the same period. The rats were euthanized, and the extensor digitorum longus (EDL) muscles from both hind limbs were removed and immediately weighed. Glutamine and glutamate concentrations were measured, and histological, signaling protein contents, and mRNA expression analyses were performed. RESULTS: Supplementation with free L-glutamine increased the glutamine concentration in the EDL muscle in the C group. The glutamate concentration was augmented in the EDL muscles from T rats. The EDL muscle mass did not change, but a significant rise was reported in the cross-sectional area (CSA) of the fibers in the three experimental groups. The levels of the phosphorylated proteins (pAkt/Akt, pp70S6K/p70S6K, p4E-BP1/4E-BP1, and pS6/S6 ratios) were significantly increased in EDL muscles of G rats, and the activation of p4E-BP1 was present in T rats. The fiber CSAs of the EDL muscles in T, G, and GT rats were increased compared to the C group. These changes were accompanied by a reduction in the 26 proteasome activity of EDL muscles from T rats. CONCLUSION: Five weeks of GS and/or RET induced muscle hypertrophy, as indicated by the increased CSAs of the EDL muscle fibers. The increase in CSA was mediated via the upregulated phosphorylation of Akt, 4E-BP1, p70S6k, and S6 in G animals and 4E-BP1 in T animals. In the EDL muscles from T animals, a decrease in proteasome activity, favoring a further increase in the CSA of the muscle fibers, was reported.


Sujet(s)
Glutamine , Conditionnement physique d'animal , Rats , Animaux , Glutamine/pharmacologie , Glutamine/métabolisme , Ribosomal Protein S6 Kinases, 70-kDa/métabolisme , Protéines proto-oncogènes c-akt/métabolisme , Proteasome endopeptidase complex/métabolisme , Rat Wistar , Muscles squelettiques/métabolisme , Hypertrophie , Compléments alimentaires , Glutamates/pharmacologie , Conditionnement physique d'animal/physiologie
12.
FEBS Open Bio ; 13(9): 1709-1722, 2023 09.
Article de Anglais | MEDLINE | ID: mdl-37470707

RÉSUMÉ

Autophagy plays a vital role in cell homeostasis by eliminating nonfunctional components and promoting cell survival. Here, we examined the levels of autophagy signaling proteins after 7 days of overload hypertrophy in the extensor digitorum longus (EDL) and soleus muscles of control and diabetic rats. We compared control and 3-day streptozotocin-induced diabetic rats, an experimental model for type 1 diabetes mellitus (T1DM). EDL muscles showed increased levels of basal autophagy signaling proteins. The diabetic state did not affect the extent of overload-induced hypertrophy or the levels of autophagy signaling proteins (p-ULK1, Beclin-1, Atg5, Atg12-5, Atg7, Atg3, LC3-I and II, and p62) in either muscle. The p-ULK-1, Beclin-1, and p62 protein expression levels were higher in the EDL muscle than in the soleus before the hypertrophic stimulus. On the contrary, the soleus muscle exhibited increased autophagic signaling after overload-induced hypertrophy, with increases in Beclin-1, Atg5, Atg12-5, Atg7, Atg3, and LC3-I expression in the control and diabetic groups, in addition to p-ULK-1 in the control groups. After hypertrophy, Beclin-1 and Atg5 levels increased in the EDL muscle of both groups, while p-ULK1 and LC3-I increased in the control group. In conclusion, the baseline EDL muscle exhibited higher autophagy than the soleus muscle. Although TDM1 promotes skeletal muscle mass loss and strength reduction, it did not significantly alter the extent of overload-induced hypertrophy and autophagy signaling proteins in EDL and soleus muscles, with the two groups exhibiting different patterns of autophagy activation.


Sujet(s)
Diabète expérimental , Rats , Animaux , Bécline-1/métabolisme , Diabète expérimental/métabolisme , Muscles squelettiques/métabolisme , Hypertrophie/métabolisme , Autophagie
13.
Gene ; 875jul.2023.
Article de Anglais | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1444289

RÉSUMÉ

Familial hypercholesterolemia (FH) is a monogenic disease characterized by high plasma low-density lipoprotein cholesterol (LDL-c) levels and increased risk of premature atherosclerotic cardiovascular disease. Mutations in FH-related genes account for 40% of FH cases worldwide. In this study, we aimed to assess the pathogenic variants in FH-related genes in the Brazilian FH cohort FHBGEP using exon-targeted gene sequencing (ETGS) strategy. FH patients (n = 210) were enrolled at five clinical sites and peripheral blood samples were obtained for laboratory testing and genomic DNA extraction. ETGS was performed using MiSeq platform (Illumina). To identify deleterious variants in LDLR, APOB, PCSK9, and LDLRAP1, the long-reads were subjected to Burrows-Wheeler Aligner (BWA) for alignment and mapping, followed by variant calling using Genome Analysis Toolkit (GATK) and ANNOVAR for variant annotation. The variants were further filtered using in-house custom scripts and classified according to the American College Medical Genetics and Genomics (ACMG) guidelines. A total of 174 variants were identified including 85 missense, 3 stop-gain, 9 splice-site, 6 InDel, and 71 in regulatory regions (3'UTR and 5'UTR). Fifty-two patients (24.7%) had 30 known pathogenic or likely pathogenic variants in FH-related genes according to the American College Medical and Genetics and Genomics guidelines. Fifty-three known variants were classified as benign, or likely benign and 87 known variants have shown uncertain significance. Four novel variants were discovered and classified as such due to their absence in existing databases. In conclusion, ETGS and in silico prediction studies are useful tools for screening deleterious variants and identification of novel variants in FH-related genes, they also contribute to the molecular diagnosis in the FHBGEP cohort.

14.
Clin Sci (Lond) ; 137(10): 807-821, 2023 05 31.
Article de Anglais | MEDLINE | ID: mdl-37219940

RÉSUMÉ

Lymphocytes act as regulatory and effector cells in inflammation and infection situations. A metabolic switch towards glycolytic metabolism predominance occurs during T lymphocyte differentiation to inflammatory phenotypes (Th1 and Th17 cells). Maturation of T regulatory cells, however, may require activation of oxidative pathways. Metabolic transitions also occur in different maturation stages and activation of B lymphocytes. Under activation, B lymphocytes undergo cell growth and proliferation, associated with increased macromolecule synthesis. The B lymphocyte response to an antigen challenge requires an increased adenosine triphosphate (ATP) supply derived mainly through glycolytic metabolism. After stimulation, B lymphocytes increase glucose uptake, but they do not accumulate glycolytic intermediates, probably due to an increase in various metabolic pathway 'end product' formation. Activated B lymphocytes are associated with increased utilization of pyrimidines and purines for RNA synthesis and fatty acid oxidation. The generation of plasmablasts and plasma cells from B lymphocytes is crucial for antibody production. Antibody production and secretion require increased glucose consumption since 90% of consumed glucose is needed for antibody glycosylation. This review describes critical aspects of lymphocyte metabolism and functional interplay during activation. We discuss the primary fuels for the metabolism of lymphocytes and the particularities of T and B cell metabolism, including the differentiation of lymphocytes, stages of development of B cells, and the production of antibodies.


Sujet(s)
Lymphocytes B , Métabolisme lipidique , Glycosylation , Transport biologique , Anticorps , Glucose
15.
Gene ; 875: 147501, 2023 Jul 30.
Article de Anglais | MEDLINE | ID: mdl-37217153

RÉSUMÉ

Familial hypercholesterolemia (FH) is a monogenic disease characterized by high plasma low-density lipoprotein cholesterol (LDL-c) levels and increased risk of premature atherosclerotic cardiovascular disease. Mutations in FH-related genes account for 40% of FH cases worldwide. In this study, we aimed to assess the pathogenic variants in FH-related genes in the Brazilian FH cohort FHBGEP using exon-targeted gene sequencing (ETGS) strategy. FH patients (n = 210) were enrolled at five clinical sites and peripheral blood samples were obtained for laboratory testing and genomic DNA extraction. ETGS was performed using MiSeq platform (Illumina). To identify deleterious variants in LDLR, APOB, PCSK9, and LDLRAP1, the long-reads were subjected to Burrows-Wheeler Aligner (BWA) for alignment and mapping, followed by variant calling using Genome Analysis Toolkit (GATK) and ANNOVAR for variant annotation. The variants were further filtered using in-house custom scripts and classified according to the American College Medical Genetics and Genomics (ACMG) guidelines. A total of 174 variants were identified including 85 missense, 3 stop-gain, 9 splice-site, 6 InDel, and 71 in regulatory regions (3'UTR and 5'UTR). Fifty-two patients (24.7%) had 30 known pathogenic or likely pathogenic variants in FH-related genes according to the American College Medical and Genetics and Genomics guidelines. Fifty-three known variants were classified as benign, or likely benign and 87 known variants have shown uncertain significance. Four novel variants were discovered and classified as such due to their absence in existing databases. In conclusion, ETGS and in silico prediction studies are useful tools for screening deleterious variants and identification of novel variants in FH-related genes, they also contribute to the molecular diagnosis in the FHBGEP cohort.


Sujet(s)
Hyperlipoprotéinémie de type II , Proprotéine convertase 9 , Humains , Proprotéine convertase 9/génétique , Brésil , Hyperlipoprotéinémie de type II/génétique , Mutation , Exons , Récepteurs aux lipoprotéines LDL/génétique , Phénotype
16.
Viruses ; 15(4)2023 04 19.
Article de Anglais | MEDLINE | ID: mdl-37112979

RÉSUMÉ

Since December 2019, the world has been experiencing the COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and we now face the emergence of several variants. We aimed to assess the differences between the wild-type (Wt) (Wuhan) strain and the P.1 (Gamma) and Delta variants using infected K18-hACE2 mice. The clinical manifestations, behavior, virus load, pulmonary capacity, and histopathological alterations were analyzed. The P.1-infected mice showed weight loss and more severe clinical manifestations of COVID-19 than the Wt and Delta-infected mice. The respiratory capacity was reduced in the P.1-infected mice compared to the other groups. Pulmonary histological findings demonstrated that a more aggressive disease was generated by the P.1 and Delta variants compared to the Wt strain of the virus. The quantification of the SARS-CoV-2 viral copies varied greatly among the infected mice although it was higher in P.1-infected mice on the day of death. Our data revealed that K18-hACE2 mice infected with the P.1 variant develop a more severe infectious disease than those infected with the other variants, despite the significant heterogeneity among the mice.


Sujet(s)
COVID-19 , SARS-CoV-2 , Animaux , Humains , Souris , Modèles animaux de maladie humaine , Souris transgéniques , Pandémies , SARS-CoV-2/génétique , Virulence
17.
Nutrients ; 15(7)2023 Mar 31.
Article de Anglais | MEDLINE | ID: mdl-37049548

RÉSUMÉ

Herein, we investigated the effect of fish oil supplementation combined with a strength-training protocol, for 6 weeks, on muscle damage induced by a single bout of strength exercise in untrained young men. Sixteen men were divided into two groups, supplemented or not with fish oil, and they were evaluated at the pre-training period and post-training period. We investigated changes before and 0, 24, and 48 h after a single hypertrophic exercise session. Creatine kinase (CK) and lactate dehydrogenase (LDH) activities, plasma interleukin-6 (IL-6) and C-reactive protein (CRP) levels, and the redox imbalance were increased in response to the single-bout session of hypertrophic exercises at baseline (pre-training period) and decreased during the post-training period in the control group due to the repeated-bout effect (RBE). The fish oil supplementation exacerbated this reduction and improved the redox state. In summary, our findings demonstrate that, in untrained young men submitted to a strength-training protocol, fish oil supplementation is ideal for alleviating the muscle injury, inflammation, and redox imbalance induced by a single session of intense strength exercises, highlighting this supplementation as a beneficial strategy for young men that intend to engage in strength-training programs.


Sujet(s)
Maladies musculaires , Entraînement en résistance , Humains , Huiles de poisson/pharmacologie , Entraînement en résistance/méthodes , Compléments alimentaires , Oxydoréduction , Muscles squelettiques , Force musculaire
19.
Proc Natl Acad Sci U S A ; 120(4): e2211933120, 2023 01 24.
Article de Anglais | MEDLINE | ID: mdl-36656866

RÉSUMÉ

Metformin is the most prescribed drug for DM2, but its site and mechanism of action are still not well established. Here, we investigated the effects of metformin on basolateral intestinal glucose uptake (BIGU), and its consequences on hepatic glucose production (HGP). In diabetic patients and mice, the primary site of metformin action was the gut, increasing BIGU, evaluated through PET-CT. In mice and CaCo2 cells, this increase in BIGU resulted from an increase in GLUT1 and GLUT2, secondary to ATF4 and AMPK. In hyperglycemia, metformin increased the lactate (reducing pH and bicarbonate in portal vein) and acetate production in the gut, modulating liver pyruvate carboxylase, MPC1/2, and FBP1, establishing a gut-liver crosstalk that reduces HGP. In normoglycemia, metformin-induced increases in BIGU is accompanied by hypoglycemia in the portal vein, generating a counter-regulatory mechanism that avoids reductions or even increases HGP. In summary, metformin increases BIGU and through gut-liver crosstalk influences HGP.


Sujet(s)
Tube digestif , Glucose , Foie , Metformine , Animaux , Humains , Souris , Cellules Caco-2 , Diabète de type 2 , Glucose/métabolisme , Hypoglycémiants/pharmacologie , Foie/métabolisme , Metformine/pharmacologie , Tomographie par émission de positons couplée à la tomodensitométrie , Tube digestif/métabolisme
20.
Toxicon ; 222: 106986, 2023 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-36442690

RÉSUMÉ

Crotoxin (CTX) is a neurotoxin that is isolated from the venom of Crotalus durissus terrificus, which displays immunomodulatory, anti-inflammatory, and anti-tumoral effects. Previous research has demonstrated that CTX promotes the adherence of leukocytes to the endothelial cells in blood microcirculation and the high endothelial venules of lymph nodes, which reduces the number of blood cells and lymphocytes. Studies have also shown that these effects are mediated by lipoxygenase-derived mediators. However, the exact lipoxygenase-derived eicosanoid involved in the CTX effect on lymphocytes is yet to be characterized. As CTX stimulates lipoxin-derived mediators from macrophages and lymphocyte effector functions could be modulated by activating formyl peptide receptors, we aimed to investigate whether these receptors were involved in CTX-induced redistribution and functions of lymphocytes in rats. We used male Wistar rats treated with CTX to demonstrate that Boc2 (butoxycarbonyl-Phe-Leu-Phe-Leu-Phe), an antagonist of formyl peptide receptors, prevented CTX-induced decrease in the number of circulating lymphocytes and increased the expression of the lymphocyte adhesion molecule LFA1. CTX reduced the T and B lymphocyte functions, such as lymphocyte proliferation in response to the mitogen Concanavalin A and antibody production in response to BSA immunization, respectively, which was prevented by the administration of Boc2. Importantly, mesenteric lymph node lymphocytes from CTX-treated rats showed an increased release of 15-epi-LXA4. These results indicate that formyl peptide receptors mediate CTX-induced redistribution of lymphocytes and that 15-epi-LXA4 is a key mediator of the immunosuppressive effects of CTX.


Sujet(s)
Crotoxine , Rats , Mâle , Animaux , Crotoxine/pharmacologie , Rat Wistar , Récepteurs aux peptides formylés/métabolisme , Cellules endothéliales , Lymphocytes , Lipoxygénases/métabolisme , Lipoxygénases/pharmacologie , Crotalus/métabolisme
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