Development of nanoformulation of picroliv isolated from Picrorrhiza kurroa

Protective effect of picroside I against hepatic fibrosis in mice via sphingolipid metabolism, bile acid biosynthesis, and PPAR signaling pathway

Picroside I, a hepatoprotectant isolated from Picrorhiza kurroa Royle ex Benth and P. scrophulariiflora Pennell, can reduce liver injury in humans and animals. However, its anti-fibrosis effect remains elusive. This work aimed to explore the mechanism underlying the hepatoprotective effect of picroside I against hepatic fibrosis. Male mice (12 mice per group) were randomly divided into six groups: the control group; the model group, which received thioacetamide (TAA); the positive group, which received TAA + S-(5'-adenosyl)-l-methionine (SAMe, 10 mg/kg); the low-dose group, which received TAA + picroside I (25 mg/kg); the middle-dose group, which received TAA + picroside I (50 mg/kg); and the high-dose group, which received TAA + picroside I (75 mg/kg). Serum biochemical indicators were detected, and histological evaluation was performed. Metabolomics and proteomic analyses were conducted via liquid-chromatography coupled with tandem mass spectrometry (LC-MS/MS). Data showed that picroside I could decrease the serum levels of alanine transaminase (ALT), aspartate transaminase (AST), collagen type IV (CIV), N-terminal peptide of type III procollagen (PIIINP), laminin (LN), and hyaluronic acid (HA) and reduced fibrosis area. Picroside I altered metabolomic profiles, including energy, lipid, and glutathione (GSH) metabolism, in ice with fibrosis. Additionally, 25 differentially expressed proteins in the picroside I high-dose-treated group were reversed relative to in the model group. These proteins were involved in the sphingolipid signaling pathway, primary bile acid biosynthesis, and peroxisome proliferator-activated receptor (PPAR) signaling pathway. Moreover, this study revealed how picroside I could protect against TAA-induced liver fibrosis in mice. Results indicated that picroside I can serve as a candidate drug for hepatic fibrosis.

Picroside II protects the blood-brain barrier by inhibiting the oxidative signaling pathway in cerebral ischemia-reperfusion injury

BACKGROUND AND PURPOSE

Thrombolysis is used to improve cerebral circulation; at the same time, neuroprotective drugs such as antioxidants should also be used. The aim of these experiments was to explore the protective mechanism of an antioxidant, picroside II, on the blood-brain barrier (BBB) after cerebral ischemia-reperfusion (CI/R) injury.

METHODS

To observe the antagonistic effect of picroside II on CI/R damage, the neurological deficit score and the infarct volume were measured. To detect the protective effect of picroside II on nerve cells and the BBB, the morphology and structure of cortical brain tissue were observed, respectively. To investigate the antioxidant effect and mechanism of picroside II, reactive oxygen species (ROS) content, the activity of Nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase), and the protein levels of Nox2 and Rac-1 were detected. To investigate the protective mechanism of picroside II on the BBB, the levels of ROCK, MLCK, MMP-2 and claudin-5 were tested.

RESULTS

A higher neurological score, bigger cortex infarction, more damaged neuron structure and injured BBB, increased content of ROS and activity of NADPH oxidase, higher protein levels of Nox2, Rac-1, ROCK, MLCK and MMP-2 and lower levels of claudin-5 were observed in the model group. In the picroside group, the neurological score, neuronal damage, BBB injury, ROS content and NADPH oxidase activity were reduced (P<0.05), and the protein levels of Rac-1, Nox2, ROCK, MLCK and MMP-2 were down-regulated (P<0.05), while the expression of claudin-5 was up-regulated (P<0.05).

CONCLUSIONS

Picroside II could protect the nervous system possibly through reducing the content of ROS by down-regulating the expression of Rac-1 and Nox2 and could protect the BBB through reducing the expression of ROCK, MLCK, and MMP-2, while enhancing the expression of claudin-5.