ABSTRACT
Aim To investigate the protective role of salvianolic acid B ( Sal B ) on cardiac hypertrophy in type 2 diabetes mice , and to explore its influence on peroxisome proliferator activated receptors-α( PPARα) .Methods The type 2 diabetes melitus ( T2DM) mouse model was established by 4 weeks ' high fat diets feeding and one time STZ intraperitoneal injection .The animals were randomly divided into:control, T2DM, T2DM+SalB(100 mg· kg -1 · d-1 ) and Sal B(100 mg· kg -1 · d-1 ) groups.Eight weeks later, heart weight, tibial length, cross section area of cardiomyocytes , protein expression of PPARαin heart tissue were recorded .In vitro, high glucose and high insulin ( HGI ) were used to induce hypertrophic growth in cultured neonatal rat cardiomyocytes ( NRC-Ms) .And cell surface area , 3 H-leucine incorporation , 3 H-D-glucose uptake and PPARαprotein level were measured to observe the effect of Sal B and MK 886, a PPARαinhibitor.Results In T2DM model mice, Sal B could lower heart weight/tibial length and cross sec-tion area of cardiomyocytes , while PPARαprotein level in hearts were improved .In cultured cardiomyocytes , Sal B ( 10 ～100 μmol · L-1 ) ameliorated the in-creased levels of cell surface area ,3 H-leucine incorpo-ration and improved the decreased 3 H-D-glucose up-take and PPARαexpression induced by HGI . But those function could be abolished by MK 886.Conclu-sion Sal B ameliorates cardiac hypertrophy in T 2DM mice, which may be related to its function on PPARαactivation .
ABSTRACT
Background: C-repeat binding factors (CBFs) are transcription factors that regulate the expression of a number of genes related to abiotic stresses. Few CBF genes have been cloned from other plants but no report in papaya. In present study, a full-length cDNA, designated as CpCBF2, was cloned from papaya using in silico cloning and 5’- rapid amplification cDNA ends (RACE). Sequence analysis was performed to understand the gene function. The expression pattern of CpCBF2 in papaya under low (7ºC) and high temperature (35ºC) stresses was examined using real-time quantitative polymerase chain reaction (RT-qPCR). Results: The full-length cDNA of CpCBF2 was 986-bp, with a 762-bp open reading frame (ORF) encoding a 254 amino acid polypeptide. CpCBF2 contained several major highly conserved regions including the CBF-family signature PKRRAGRKKFQETRHP and FADSAW in its amino acid sequence. Phylogenetic tree and three-dimensional structure analysis showed that CpCBF2 had a relatively close relationship with other plant CBFs. Gene expression analysis showed that high temperature stress had little effect on the expression of CpCBF2 but low temperature repressed CpCBF2 expression. Conclusion: The results showed that CpCBF2 may involve in different roles in temperature stress tolerance. This study provided a candidate gene potentially useful for fruit temperature stress tolerance, although its function still needs further confirmation.