Catalpol

Neuroprotective and anti-inflammatory properties documented in preclinical research, particularly in Rehmannia and Plantago species. Contribution to Veronica beccabunga activity inferred from family pharmacology.

Neuroprotective in stroke and neurodegeneration models; anti-inflammatory; supports traditional use for nervous system complaints

In vivo studies in MPTP-induced Parkinson's models (mice) showed catalpol at 5–10 mg/kg restored tyrosine hydroxylase expression and improved motor function (Zhang et al., J Ethnopharmacol, 2016). A randomized controlled trial of Rehmannia-containing Liu Wei Di Huang Wan in 120 type 2 diabetes patients demonstrated significant HbA1c reduction versus placebo over 12 weeks (Huang et al., J Tradit Chin Med, 2013). In vitro studies on SH-SY5Y neuroblastoma cells confirmed catalpol reduces Aβ-induced toxicity by 40–60% via BDNF upregulation.

Improved cognitive function in Alzheimer's disease animal models. Reduced blood glucose in diabetic rats. Protected against cerebral ischemia-reperfusion injury.

Catalpol is the primary iridoid glycoside in raw Rehmannia. Animal studies demonstrate neuroprotective and anti-diabetic effects. Clinical trials of Rehmannia formulas show efficacy in diabetic conditions.

Catalpol is well-studied across multiple Scrophulariaceae and Orobanchaceae plants. Neuroprotective effects against beta-amyloid toxicity demonstrated in vitro and in MPTP-induced Parkinson's models in vivo. Hypoglycemic activity confirmed in STZ-induced diabetic rodents. Anti-inflammatory effects via NF-κB inhibition documented. Shared with Rehmannia glutinosa (Di Huang), providing a phytochemical rationale for classical pairing of Xuan Shen with Di Huang in yin-nourishing formulas.