Abstract
Sodium orthovanadate is a non-selective protein tyrosine phosphatase inhibitor that can cause several types of kidney injury, including glomerulosclerosis, inflammation, and tubular damage. Cannabis is widely known for its medicinal use, and several studies have demonstrated its anti-diabetic and anti-inflammatory properties. The current study investigated the therapeutic effect of Lebanese cannabis oil extract (COE) against sodium orthovanadate-induced nephrotoxicity both in vitro and in vivo. Sprague Dawley male rats were intraperitoneally injected with 10 mg/kg sodium orthovanadate for 10 days followed by 5 mg/kg; 10 mg/kg; or 20 mg/kg intraperitoneal injection of cannabis oil extract, starting on day 4 until day 10. The body weight of the rats was monitored during the study, and clinical parameters, including serum urea, creatinine, and electrolytes, as well as kidney and heart pathology, were measured. Conditionally immortalized cultured rat podocytes were exposed to either sodium orthovanadate or selective phosphatase inhibitors, including DUSPi (DUSP1/6 inhibitor) and SF1670 (PTEN inhibitor), in the presence or absence of cannabis oil extract. MTS and an in vitro scratch assay were used to assess podocyte cell viability and migration, respectively. Western blot analysis was used to evaluate the phosphorylation levels of AKT and p38 MAPK. Rats injected with sodium orthovanadate displayed a marked reduction in body weight and an increase in serum creatinine and urea in comparison to the control non-treated group. All doses of COE caused a significant decrease in serum urea, with a significant decrease in serum creatinine observed at a dose of 20 mg/kg. Moreover, the COE treatment of rats injected with orthovanadate (20 mg/kg) showed a marked reduction in renal vascular dilatation, scattered foci of acute tubular necrosis, and numerous mitoses in tubular cells compared to the sodium orthovanadate-treated group. The cell viability assay revealed that COE reversed cytotoxicity induced by sodium orthovanadate and specific phosphatase inhibitors (DUSPi and SF1670) in rat podocytes. The in vitro scratch assay showed that COE partially restored the migratory capacity of podocytes incubated with DUSPi and SF1670. Time-course and dose-dependent experiments showed that COE (1 μg/mL) induced a significant increase in phospho-(S473)-AKT, along with a decrease in phospho (T180 + Y182) P38 levels. The current results demonstrated that Lebanese cannabis oil possesses important kidney protective effects against sodium orthovanadate-induced renal injury.