Indian-laurel

An alkaloid-rich bark extract dosed at 50, 100 and 200 mg/kg orally for four weeks in ob/ob mice reduced body and fat weight without reducing food intake, and at 100-200 mg/kg lowered fasting glucose, HbA1c and glycated serum protein, cut fasting insulin and HOMA-IR, improved oral glucose tolerance, eased dyslipidaemia and liver steatosis, and raised hepatic glucokinase, pyruvate kinase and glycogen. Eight main alkaloids were identified by UPLC-QTOF-MS. Animal study on the bark; no human trial exists.

The extract increased osteoblast differentiation, viability and mineralisation in culture and raised BMP2, phospho-SMAD, RUNX2 and type I collagen expression, while suppressing RANKL-induced osteoclastogenesis. In a drill-hole injury model in Balb/c mice it accelerated new bone formation at 20 mg/kg over 12 days, and in ovariectomised mice the same dose over a month preserved bone microarchitecture, mineral density and strength and normalised turnover markers. Preclinical only.

A PRISMA review of 450 records yielding 19 primary studies across nine Litsea species. Litsea glutinosa was one of six species showing peripheral antinociception in the acetic acid writhing test, one of five also active in the tail-flick assay at spinal level, and one of only two active at supraspinal level in the hot plate assay. Its value for this record is as much taxonomic as pharmacological: the review keeps Litsea glutinosa and Litsea cubeba as separate entries with separate evidence bases. All the underlying studies are animal studies.

Cold methanol extracts of the leaves, screened by HPLC and conventional phytochemistry as phenol- and flavonoid-dominant, showed analgesic activity in acetic acid writhing and hot plate tests (best at 500 mg/kg), antipyretic activity against yeast-induced pyrexia, and antibacterial activity by disc diffusion, with acute toxicity testing included. This is the leaf, not the bark that constitutes the main traditional drug, and the two plant parts should not be treated as interchangeable.

Aporphine alkaloids isolated from Litsea glutinosa were tested for antiproliferative activity against cell lines, with the work framed against the plant's use in Kuuku I'yu (Cape York Peninsula, Australia) traditional medicine. In vitro screening of isolated compounds; no animal or human efficacy is claimed and none should be inferred for cancer treatment.

Screening of Litsea glutinosa bark extract for antibacterial activity, the earliest of the laboratory reports underpinning the traditional use of the bark in diarrhoea and dysentery and in poultices for infected wounds. In vitro only, on a crude extract, with no clinical endpoint.