Sympathetic nerve and vagus nerve remodeling play an important part in cardiac function post-myocardial infarction （MI）. Increasing evidence indicates that neuregulin-1 （NRG-1） improves cardiac function following ...Sympathetic nerve and vagus nerve remodeling play an important part in cardiac function post-myocardial infarction （MI）. Increasing evidence indicates that neuregulin-1 （NRG-1） improves cardiac function following heart failure. Since its impact on cardiac function and neural remodeling post-MI is poorly understood, we aimed to investigate the role of NRG-1 in autonomic nervous system remodeling post-MI. Forty-five Sprague-Dawley rats were equally randomized into three groups： sham （with the left anterior descending coronary artery exposed but without ligation）, MI （left anterior descending coronary artery ligation）, and MI plus NRG-1 （left anterior descending coronary artery ligation followed by intraperitoneal injection of NRG-1 （10 lag/kg, once daily for 7 days））. At 4 weeks after MI, echocardi- ography was used to detect the rat cardiac function by measuring the left ventricular end-systolic inner diameter, left ventricular diastolic diameter, left ventricular end-systolic volume, left ventricular end-diastolic volume, left ventricular ejection fraction, and left ventricular fractional shortening, mRNA and protein expression levels of tyrosine hydroxylase, growth associated protein-43 （neuronal specific pro- tein）, nerve growth factor, choline acetyltransferase （vagus nerve marker）, and vesicular acetylcholine transporter （cardiac vagal nerve fiber marker） in ischemic myocardia were detected by real-time PCR and western blot assay to assess autonomous nervous remodeling. After MI, the rat cardiac function deteriorated significantly, and it was significantly improved after NRG-1 injection. Compared with the MI group, mRNA and protein levels of tyrosine hydroxylase and growth associated protein-43, as well as choline acetyltransferase mRNA level significantly decreased in the MI plus NRG-1 group, while mRNA and protein levels of nerve growth factor and vesicular acetylcholine transporters, as well as choline acetyltransferase protein level slightly decreased. Our results indicate that NRG- 1 can improve cardiac function and regulate sympathetic and vagus nerve remodeling post-MI, thus reaching a new balance of the autonomic nervous system to protect the heart from injury.展开更多
Neuregulin-1 (NRG1) is a well known growth factor playing contradictory roles in myelination depending on the existing isoform. Transmembrane NRG1 acts as a promyelinating factor, while the soluble isoform inhibits my...Neuregulin-1 (NRG1) is a well known growth factor playing contradictory roles in myelination depending on the existing isoform. Transmembrane NRG1 acts as a promyelinating factor, while the soluble isoform inhibits myelination. In this perspective, we would like to emphasize this conflicting role played by NRG1 isofbrms regarding their roles in myelination, remyelination and the entire process of peripheral nerve regeneration.展开更多
Neuregulin-1 type Ⅲ is a key regulator in Schwann cell proliferation, committing to a myelinat- ing fate and regulating myelin sheath thickness. However, the expression pattern of neuregulin- 1 type III in the periph...Neuregulin-1 type Ⅲ is a key regulator in Schwann cell proliferation, committing to a myelinat- ing fate and regulating myelin sheath thickness. However, the expression pattern of neuregulin- 1 type III in the peripheral nervous system during developmental periods （such as the premyelin- ating stage, myelinating stage and postmyelinating stage） has rarely been studied. In this study, dorsal root ganglia were isolated from rats between postnatal day 1 and postnatal day 56. The expression pattern of neuregulin-1 type III in dorsal root ganglia neurons at various develop- mental stages were compared by quantitative real-time polymerase chain reaction, western blot assay and immunofluorescent staining. The expression of neuregulin-I type Ⅲ mRNA reached its peak at postnatal day 3 and then stabilized at a relative high expression level from postnatal day 3 to postnatal day 56. The expression of neuregulin-1 type III protein increased gradually from postnatal day 1, reached a peak at postnatal day 28, and then decreased at postnatal day 56. Immunofluorescent staining results showed a similar tendency to western blot assay results. Experimental findings indicate that the expression of neuregulin-1 type III in rat dorsal root ganglion was increased during the premyelinating （from postnatal day 2 to postnatal day 5） and myelinating stage （from postnatal day 5 to postnatal day 10）, but remained at a high level in the postmyelinating stage （after postnatal day 10）.展开更多
基金supported by a grant from the National Key Basic Research Development Program,the“973”Program,No.2012CB518604the National Natural Science Foundation of China,No.81260052+1 种基金the Natural Science Foundation of Hubei Province,No.2014CKB497,2014BKB075,and 2015BKA339the Natural Science Foundation of Henan Province of China,No.201602262
文摘Sympathetic nerve and vagus nerve remodeling play an important part in cardiac function post-myocardial infarction （MI）. Increasing evidence indicates that neuregulin-1 （NRG-1） improves cardiac function following heart failure. Since its impact on cardiac function and neural remodeling post-MI is poorly understood, we aimed to investigate the role of NRG-1 in autonomic nervous system remodeling post-MI. Forty-five Sprague-Dawley rats were equally randomized into three groups： sham （with the left anterior descending coronary artery exposed but without ligation）, MI （left anterior descending coronary artery ligation）, and MI plus NRG-1 （left anterior descending coronary artery ligation followed by intraperitoneal injection of NRG-1 （10 lag/kg, once daily for 7 days））. At 4 weeks after MI, echocardi- ography was used to detect the rat cardiac function by measuring the left ventricular end-systolic inner diameter, left ventricular diastolic diameter, left ventricular end-systolic volume, left ventricular end-diastolic volume, left ventricular ejection fraction, and left ventricular fractional shortening, mRNA and protein expression levels of tyrosine hydroxylase, growth associated protein-43 （neuronal specific pro- tein）, nerve growth factor, choline acetyltransferase （vagus nerve marker）, and vesicular acetylcholine transporter （cardiac vagal nerve fiber marker） in ischemic myocardia were detected by real-time PCR and western blot assay to assess autonomous nervous remodeling. After MI, the rat cardiac function deteriorated significantly, and it was significantly improved after NRG-1 injection. Compared with the MI group, mRNA and protein levels of tyrosine hydroxylase and growth associated protein-43, as well as choline acetyltransferase mRNA level significantly decreased in the MI plus NRG-1 group, while mRNA and protein levels of nerve growth factor and vesicular acetylcholine transporters, as well as choline acetyltransferase protein level slightly decreased. Our results indicate that NRG- 1 can improve cardiac function and regulate sympathetic and vagus nerve remodeling post-MI, thus reaching a new balance of the autonomic nervous system to protect the heart from injury.
文摘Neuregulin-1 (NRG1) is a well known growth factor playing contradictory roles in myelination depending on the existing isoform. Transmembrane NRG1 acts as a promyelinating factor, while the soluble isoform inhibits myelination. In this perspective, we would like to emphasize this conflicting role played by NRG1 isofbrms regarding their roles in myelination, remyelination and the entire process of peripheral nerve regeneration.
基金supported by grants from the National Program on Key Basic Research Project of China(973 Program),No.2014CB542206the National Natural Science Foundation of China,No.81201389,30973052Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China,No.IRT13051
文摘Neuregulin-1 type Ⅲ is a key regulator in Schwann cell proliferation, committing to a myelinat- ing fate and regulating myelin sheath thickness. However, the expression pattern of neuregulin- 1 type III in the peripheral nervous system during developmental periods （such as the premyelin- ating stage, myelinating stage and postmyelinating stage） has rarely been studied. In this study, dorsal root ganglia were isolated from rats between postnatal day 1 and postnatal day 56. The expression pattern of neuregulin-1 type III in dorsal root ganglia neurons at various develop- mental stages were compared by quantitative real-time polymerase chain reaction, western blot assay and immunofluorescent staining. The expression of neuregulin-I type Ⅲ mRNA reached its peak at postnatal day 3 and then stabilized at a relative high expression level from postnatal day 3 to postnatal day 56. The expression of neuregulin-1 type III protein increased gradually from postnatal day 1, reached a peak at postnatal day 28, and then decreased at postnatal day 56. Immunofluorescent staining results showed a similar tendency to western blot assay results. Experimental findings indicate that the expression of neuregulin-1 type III in rat dorsal root ganglion was increased during the premyelinating （from postnatal day 2 to postnatal day 5） and myelinating stage （from postnatal day 5 to postnatal day 10）, but remained at a high level in the postmyelinating stage （after postnatal day 10）.
