To investigate the effect of total flavonoids from Patrinia on neuroprotection in rats with ischemic stroke (IS) by Rat sarcoma virus oncogene homolog (Ras) homolog gene family member (Rho) A/Rho-associated kinase (ROCK) signaling pathway.

The IS rat model was established by the suture method, and was randomly divided into B group (IS), C group (total senna flavonoids low dose), D group (total senna flavonoids high dose), E group (positive drug), F group (high dose of total senna flavonoids+U-46619F) and A group (the sham operation), where group A and group B were given intragastric and intraperitoneal injections of normal saline; group C was given 100 mg·kg^-1 total senna flavonoids by intragastric administration; group D was given 200 mg·kg^-1 total senna flavonoids by intragastric administration; group E was given 1.0 mg·kg^-1 nimodipine by intraperitoneal injection; group F was given intragastric administration of 200 mg·kg^-1 total senna flavonoids and 30 μg·kg^-1 U-46619 by intraperitoneal injection; each group was administered once a day for two consecutive weeks. After the intervention, the modified neurological severity (mNSS) score was used to evaluate the nerve injury; the triphenyltetrazolium chloride staining (TTC) was used to detect the ratio of cerebral infarction area; the brain tissue was separated, and hematoxylin-eosin was used for pathological changes; the expression of nerve growth factor (NGF) was detected by immunohistochemistry; the apoptosis changes of striatal dopaminergic neurons were detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling method (TUNEL); the relative expression levels of Bcl-2 related X protein (Bax), RhoA, ROCK and B-cell lymphoma factor 2 (Bcl-2) proteins were detected by immunoblotting.

The nerve injury scores for groups A, B, D, E, and F were (0.15±0), (11.24±1.26), (4.06±0.42), (3.52±0.38) and (7.18±0.73) points, respectively; the ratio of infarct area were (0±0)%, (27.86±2.81)%, (11.57±1.27)%, (12.07±1.24)% and (18.07±1.88)%; the relative expression levels of NGF were 34.11±3.51, 15.86±1.61, 32.07±3.28, 32.11±3.32 and 22.87±2.31; the apoptosis of dopaminergic neurons were (6.57±0.68)%, (27.81±2.82)%, (12.75±1.31)%, (12.52±1.27)% and (20.47±2.11)%; the aforementioned indicators of group B were compared with those of group A; those of groups C and D were compared with group B; and those of group F were compared with group D, all showing statistically significant differences (all P<0.05).

The total flavonoids of Cynanchum paniculatum have neuroprotective effects on IS rats, and the mechanism may be related to the activation of the RhoA/ROCK signaling pathway.