Winged prickly-ash

The only published human trial of this species. Eighty-two healthy adults aged 30 to 55 took 80 mg of a Zanthoxylum armatum extract standardised to hydroxy-alpha-sanshool, limonene, linalool and methyl cinnamate, or placebo, for 56 days, with cognitive and near-infrared spectroscopy assessments acutely on day 1 and again on day 56. Acutely the extract improved speed of attention at 1 and 3 hours and reduced false alarms on a rapid visual information processing task, but name-to-face recall accuracy was worse than placebo. After 56 days global speed of performance was faster at several timepoints and self-rated mental fatigue was lower, with no domain-specific gain in memory or attention accuracy. The haemodynamic response during task performance was reduced, which the authors read as increased neural efficiency rather than reduced perfusion; resting cerebral blood flow was unchanged. The trial was in healthy volunteers on a proprietary standardised extract and does not speak to the traditional decocted drug.

Methanol extracts of fruit, bark and leaf were tested separately in isolated rabbit jejunum, trachea and thoracic aortic rings and in castor-oil-induced diarrhoea in mice. Fruit and bark extracts gave 75 and 52 percent protection against diarrhoea against 96 percent for verapamil. In jejunum the extracts inhibited spontaneous and high-potassium precontractions with EC50 values between 0.5 and 3.1 mg/mL; in aortic rings the fruit extract fully relaxed phenylephrine-induced contraction at an EC50 of 0.8 mg/mL with only partial inhibition of the high-potassium response. Butyrylcholinesterase inhibition was 82.6 percent for bark, 50.8 percent for fruit and 37.5 percent for leaf. No acute toxicity was seen up to 3 g/kg. The authors attribute the spasmolysis to calcium channel blockade. Note that the paper reports percentage inhibition for the extracts but an IC50 only for the reference standard, so extract potency is not directly comparable.

Leaf and bark extracts inhibited alpha-glucosidase in vitro by 96.6 and 93.6 percent. In alloxan-diabetic mice, extracts at 500 mg/kg for 15 days significantly lowered fasting blood glucose against diabetic controls, with the leaf extract most effective, and improved haemoglobin, urea, creatinine, cholesterol and triglycerides; LDL fell. Glibenclamide 10 mg/kg was the comparator. This is a small alloxan-model study at a high single dose with no dose-response and no clinical follow-up, so it supports a mechanism rather than an efficacy claim.

Methanol extracts of fruit, bark and leaf inhibited growth of MCF-7, MDA-MB-468 and Caco-2 lines dose-dependently from 200 micrograms per millilitre upward, but the crude saponin fractions were markedly more active, reaching 95 percent inhibition of MDA-MB-468 for the fruit saponins against 71 percent for actinomycin-D. DAPI staining showed nuclear fragmentation and chromatin condensation consistent with apoptosis. This is cell-line screening of crude fractions with no normal-cell selectivity control reported and no in vivo work, and it should not be read as an anticancer indication.

Bioassay-guided fractionation of the methanol extract of dried pericarp from Nepalese material yielded four new isobutylhydroxyamides, timuramides A to D, alongside ZP-amides A, C, D and E and hydroxy-alpha- and hydroxy-beta-sanshool. Tested against an NF1- and p53-deficient mouse glioma line, the amides showed moderate growth inhibition, hydroxy-beta-sanshool being the most active at around 65 percent. The value of this paper for a clinical database is chiefly that it establishes the alkylamide profile of the pericarp of this species specifically, rather than importing it from Zanthoxylum bungeanum or Zanthoxylum piperitum.

Zanthoxylum alatum Roxb. is a synonym of Zanthoxylum armatum DC., so this is a safety study of the same species. The pericarp essential oil, dominated by linalool at about 56 percent and methyl cinnamate at about 20 percent, gave an acute oral LD50 of 6124 microlitres per kilogram in mice, which the authors characterise as negligible mammalian toxicity, alongside antifungal, antiaflatoxigenic and antioxidant activity in a black-pepper preservation model. This is an acute-toxicity figure for the volatile oil only; it says nothing about repeated dosing, about the bark or root drug, or about the alkaloid-bearing fractions.