Gap 27

Cell lines

Osteoclasts

Preparation Method

Mechanically harvested osteoclasts from the long bones of 1 or 2-day-old Sprague-Dawley rat pups were allowed to attach to sonicated bovine cortical bone slices (0.5cm²). After 30min, the non-attached cells were rinsed away, and the remaining cells on the bone slices were cultured in three groups: control, heptanol and Gap 27. The control group was cultured in DMEM (Dulbecco's modified Eagle's medium) buffered with 20mM Hepes and containing 0.84g of sodium bicarbonate/liter, 2mM L-glutamine, 100 IU of penicillin/ml, 100µg of streptomycin/ml and 7% heatinactivated fetal calf serum (FCS), which medium will be later referred to as DMEM-FCS. The heptanol group was cultured in medium with 0.15% ethanol and 3mM heptanol in DMEM-FCS. Third group of bone cells, Gap 27 peptide group, was cultured with Gap 27 peptide at concentration 500µM in DMEM-FCS. In all the three groups cells were cultured for 48h, after which the cultures were stopped by fixing the cells and bone slices with freshly made or refrigerated 3% paraformaldehyde (PFA) and 2% sucrose in PBS for 10min at room temperature. The cells were stained for tartrate-resistant acid phosphatase (TRAP), a commonly accepted marker of osteoclasts, using a TRAP kit according to the manufacturer's instruction.

Reaction Conditions

500µM; 48h

Applications

Gap 27 caused a remarked decrease in the number of both TRAP-positive mononuclear and multinucleated rat osteoclasts cultured on bovine bone slices.

Animal models

Sprague-Dawley rats

Preparation Method

Highoutput heart failure was induced by volume overload using the arterio-venous fistula model (AV-Shunt) in adult male rats. Four weeks after AV-Shunt surgery, the Cx43 mimetic peptide Gap 27 (1µg/kg) or scrambled peptide, were administered via osmotic minipumps (AV-ShuntGap 27 or AV-ShuntScr) for 4 weeks. Cardiac volumes, arrhythmias, function and remodeling were determined at 8 weeks after AV-Shunt surgeries.

Dosage form

1µg/kg; 4 week; osmotic minipumps

Applications

Gap 27 treatment significantly slowed the progression of cardiac deterioration in rats, and intraventricular pressure-volume loop measurements showed a significant improvement in cardiac function.

References:
[1] Ilvesaro J, Tavi P, Tuukkanen J. Connexin-mimetic peptide Gap 27 decreases osteoclastic activity[J]. BMC musculoskeletal disorders, 2001, 2(1): 10.
[2]Lucero C M, Andrade D C, Toledo C, et al. Cardiac remodeling and arrhythmogenesis are ameliorated by administration of Cx43 mimetic peptide Gap27 in heart failure rats[J]. Scientific Reports, 2020, 10(1): 6878.