RESUMO
This study investigated the effects of angiotensin II (AngII) intervention, using captopril and losartan, on the expression of matrix metalloproteinase-2 (MMP-2), MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), and collagen in rats with pulmonary hypertension, in an effort to understand mechanisms underlying pulmonary vascular remodeling. A total of 40 male Sprague-Dawley rats were randomly divided into normal group, model group, captopril group, and losartan group. After 5 weeks, the mean pulmonary arterial pressure (mPAP), right ventricular index, and neointima formation in each group were determined. Immunohistochemical analysis was performed to determine the degree of pulmonary arterial muscularization as well as MMP-2, MMP-9, and TIMP-1 protein expression in lung tissue. Real-time fluorescent quantitative PCR was used to detect MMP2, MMP9, TIMP1, COL1A1, and COL4A1 mRNA expression. Picro-sirius red staining was performed to detect collagen protein expression. Neointima formation was observed in the model group. Moreover, the mPAP, right ventricular index, degree of arterial muscularization, and collagen deposition, as well as mRNA and protein expression of MMP2, MMP9, and TIMP1 were significantly higher than those in the other groups (P < 0.05). The mPAP, right ventricular index, degree of arterial muscularization, and mRNA and protein expression in the captopril and losartan groups were significantly decreased compared with those of the model group (P < 0.05). AngII regulates MMP-2, MMP-9, and TIMP-1 expression and affects collagen deposition. Thus, this hormone is involved in pulmonary vascular remodeling, indicating a possible mechanism that can be targeted in pulmonary hypertension intervention.
Assuntos
Angiotensina II/farmacologia , Colágeno Tipo IV/metabolismo , Colágeno Tipo I/metabolismo , Hipertensão Pulmonar/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Animais , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Colágeno Tipo IV/genética , Modelos Animais de Doenças , Hipertensão Pulmonar/tratamento farmacológico , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Artéria Pulmonar/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Inibidor Tecidual de Metaloproteinase-1/genéticaRESUMO
The genus Lolium is one of the most important groupings of temperate forage grasses, including about eight recognized species that are native to some temperate and subtropical regions of the northern hemisphere. We examined genetic relationships among 18 accessions representing all Lolium species using RAPD markers. Among 50 random primers that we screened, 13 gave reproducible amplification banding patterns. Each of these 13 primers generated 19-43 scorable fragments. A total of 367 RAPD fragments were detected, of which 95.9% were polymorphic across all the Lolium accessions. Dice's coefficient of dissimilarity ranged from 0.016 to 0.622, which is indicative of substantial genetic variations in these Lolium accessions. A neighbor-joining cluster analysis, with bootstrap permutation, produced an unrooted dendrogram, which grouped 18 accessions into two main clades, supporting high bootstrap values (98 and 96%). The first clade included the self-pollinated species, L. persicum, L. temulentum, L. remotum, and L. subulatum. The cross-pollinated species, i.e., L. multiflorum, L. perenne, L. rigidum, and L. canariense, composed the second clade, in which L. canariense formed a distinct subclade, indicating its higher genetic separation from other allogamous species. The value of r = 0.97 in the Mantel test for cophenetic correlation applied to the cluster analysis indicated the high degree of fit of the accessions to a group. A principal coordinate analysis, whose first three coordinates explained 72.6% of the variation, showed similar groupings as in the cluster analysis. The genetic relationships estimated by the polymorphism of RAPD markers are basically in agreement with those previously inferred with other genetic markers.
Assuntos
Marcadores Genéticos , Lolium/genética , Filogenia , Técnica de Amplificação ao Acaso de DNA Polimórfico , DNA de Plantas , Polimorfismo Genético , Análise de Componente PrincipalRESUMO
Fifty-five wild accessions of bermudagrass (Cynodon dactylon) were collected from southwest China (Sichuan, Chongqing, Yunnan, Guizhou, and Tibet), and their genetic diversity was analyzed using simple sequence repeat markers. A total of 267 polymorphic bands were detected with 18 primer combinations. The genetic similarity among the accessions ranged from 0.688 to 0.894 with an average of 0.797. All 55 wild accessions were clustered into 7 eco-geographic groups. Our data showed that the dendrogram was almost in accordance with geographic distribution, and accessions from the same collection sites tended to be clustered into the same group. A genetic differentiation analysis revealed that the percentage of genetic variance was 70.07 and 29.93% within and among groups, respectively. Finally, we discuss the implications of these results for C. dactylon in southwest China.