Recombinant expressed vector pET32a (+) S constructed by ligation independent cloning

An efficient method for integration of PCR fragments into adjacent or overlapping restriction sites during gene cloning

In the present work, a simple and straightforward method was developed to clone any PCR-amplified products into restriction sites that are very close, adjacent or overlapping in the expression vector. The novelty of the methodology involves a crucial primer-designing step by adding appropriate overhangs to the 5' ends of primers based on the multiple cloning sites (MCS) (polylinker) region of expression vector. After PCR amplification, actual cloning is performed not in adjacent RE sites, but in sites that are little distant in the MCS. However, the sites lost during this cloning step are maintained intact since they are provided by the cloned PCR product (through the primer overhangs). Gene for green fluorescent protein (GFP) was cloned and expressed employing this strategy to demonstrate its simplicity. This method is highly useful for vector modification without losing the restriction sites present in the MCS.

Sugemule-3 Protects against Isoprenaline-induced Cardiotoxicity In vitro

Background:

Sugemule-3 (SD) is a traditional Chinese medicine with protective effect of myocardium. However, the underlying mechanisms of the effect had not been elucidated.

Materials and Methods:

In the present study, the serum of SD was prepared. A model of β-adrenergic agonist isoprenaline (ISO)-induced H9c2 cardiomyocytes injury was established in vitro. The changes in cell viability were examined to determine the available concentration of ISO and serum of SD. ELISA, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay, and flow cytometry were used to detect the effect of serum of SD on oxidative stress and apoptosis. The expression levels of the mitochondria-dependent apoptotic pathway and mitogen-activated protein kinase signalling-related proteins were analyzed.

Results:

Incubation with different dose of ISO (0.015, 0.01, 0.005, and 0.0025 mol/L) for 24 h caused dose-dependent loss of cell viability and 0.01 mol/L of ISO approximately reduced the cell viability to 50%. Pretreatment with 50 μ mol/L serum of SD effectively decreased the levels of ISO-induced cell toxicity. Serum of SD relived ISO-induced oxidative stress and apoptosis in H9c2 cardiomyocytes. A further mechanism study indicated that serum of SD inhibited the mitochondria-dependent apoptotic pathways and regulated the expression levels of Bcl-2 family. ISO activated ERK and P38, whereas serum of SD inhibited their activation.

Conclusion:

Serum of SD inhibits the ISO-induced activation of the mitochondria-dependent apoptotic pathway, oxidative stress, and ERK, P38 inactivation. Serum of SD is used for the treatment of ISO-induced cardiomyopathy.

SUMMARY

The serum of SD pretreatment significantly ameliorated ISO-induced H9c2 cardiomyocytes injuries.

The protective effect related with apoptosis and oxidative stress

Inhibition of MAPK pathway was involed in serum of SD induced cardioprotection.

The serum of SD is used for the treatment of ISO-induced cardiomyopathy.

Abbreviations used: ELISA: Enzyme-linked Immunosorbent Assay; TUNEL: TdT-mediated dUTP nick end labeling; MTT: 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, DMSO: dimethyl sulfoxide; MDA: Malondialdehyde; SOD: Superoxide Dismutase; GSH-Px: Glutathione peroxidase.