RESUMO
BACKGROUND AND AIM: Regulatory T cells (Tregs) play an important role in cardiovascular complications with the immune response. However, the role of Tregs in high fat diet (HFD)-induced myocardial fibrosis has not been fully elucidated to date. Therefore, we investigated whether HFD suppresses Tregs activation in the myocardium of spontaneously hypertensive rats (SHRs), which aggregates myocardial fibrosis. METHODS AND RESULTS: Eight-week-old male SHRs were fed to either HFD or control diet (CHO) groups for 12 weeks. We measured Tregs (CD4+FoxP3+) in the heart and mediastinal lymph nodes (LNs). The flow cytometry analysis confirmed that SHR-HFD exhibited a decreased Tregs compared to that of SHR-CHO in the heart and mediastinal LNs. Furthermore, the CD4 and FoxP3 antigens were used in the immunofluorescence microscopy of Tregs in the heart tissues. In the heart, dual staining for the Treg population was increased more in SHR-CHO than it was in SHR-HFD rats. In line with these findings, SHR-HFD significantly exacerbated myocardial fibrosis. CONCLUSION: We found that diet-induced obesity typically showed an exacerbated myocardial fibrosis and down-regulation of Tregs pathway in the heart and mediastinal LNs. Therefore, we suggest that the up-regulation of Tregs may be a promising therapeutic approach to preventing obesity induced heart failure.
Assuntos
Cardiomiopatias/imunologia , Dieta Hiperlipídica , Miocárdio/imunologia , Obesidade/imunologia , Linfócitos T Reguladores/imunologia , Animais , Biomarcadores/metabolismo , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Modelos Animais de Doenças , Regulação para Baixo , Fibrose , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Linfonodos/imunologia , Masculino , Mediastino , Miocárdio/metabolismo , Miocárdio/patologia , Obesidade/metabolismo , Obesidade/patologia , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Linfócitos T Reguladores/metabolismoRESUMO
The complete genomic RNAs of two Korean sacbrood virus (SBV) strains, which infect the honey bee, Apis mellifera, were sequenced. The two sequences (AmSBV-Kor19, AmSBV-Kor21) were distinguished by the presence or absence of a PstI restriction site. These strains comprised of 8784 bp and 8835 bp; contained a single large ORF (179-8707 and 179-8758) encoding 2843 and 2860 amino acids, respectively. Deduced amino acid sequences comparison with some insect viruses showed that regions of helicase, protease and RdRp domains; structural genes were located at the 5' end and non-structural genes at the 3' end. Multiple sequence alignment showed that AmSBV-Kor19 was missing a section between nucleotides 2311 and 2361 (present in SBV-UK and CSBV) but was similar to that of the Korean SBV strain that infects A. cerana (AcSBV-Kor). The differences in the AmSBV-Kor19 strain may be the result of the virus adapting to a different host.
