Salvihispin A and its glycoside, two neo -clerodane diterpenoids with neurotrophic activities from Salvia hispanica L

Neurotrophic Natural Products

Neurotrophins (NGF, BDNF, NT3, NT4) can decrease cell death, induce differentiation, as well as sustain the structure and function of neurons, which make them promising therapeutic agents for the treatment of neurodegenerative disorders. However, neurotrophins have not been very effective in clinical trials mostly because they cannot pass through the blood-brain barrier owing to being high-molecular-weight proteins. Thus, neurotrophin-mimic small molecules, which stimulate the synthesis of endogenous neurotrophins or enhance neurotrophic actions, may serve as promising alternatives to neurotrophins. Small-molecular-weight natural products, which have been used in dietary functional foods or in traditional medicines over the course of human history, have a great potential for the development of new therapeutic agents against neurodegenerative diseases such as Alzheimer's disease. In this contribution, a variety of natural products possessing neurotrophic properties such as neurogenesis, neurite outgrowth promotion (neuritogenesis), and neuroprotection are described, and a focus is made on the chemistry and biology of several neurotrophic natural products.

Neo-clerodane Diterpenoids with Hypoglycemic Effects in Vivo from the Aerial Parts of Salvia hispanica L

A new neo-clerodane diterpenoid, salvihispin H (1), and six known ones (2-7) were identified from the aerial parts of Salvia hispanica L. The structure and absolute configuration of 1 were elucidated by extensive analysis of spectroscopic (¹ H, ¹³ C, and 2D NMR, and HR-ESI-MS) and single-crystal X-ray diffraction data. The anti-diabetic effects of salvihispin H (1) and salvifaricin (2) were evaluated in diabetic db/db mice. The data showed that 1 and 2 could significantly reduce fasting blood glucose level and improve insulin resistance, and compound 1 exerted glucose-lowering effect more quickly than metformin. In addition, 1 and 2 could also reduce serum TG level in db/db mice. These results demonstrated that compounds 1 and 2 could be considered as potent candidates for the therapy of type 2 diabetes mellitus (T2DM).

Rearranged neoclerodane diterpenoids from the aerial parts of Salvia hispanica L

Six new rearranged neoclerodane diterpenoids (1-6), as well as three known ones, were obtained from the aerial part of Salvia hispanica L. Their structures were elucidated by extensive analysis of spectroscopic data (1D, 2D NMR, and HRESIMS) and Mosher's method. The absolute configurations of 1, 2, and 4 were determined by single-crystal X-ray diffraction analysis. All isolated compounds were evaluated for their cardioprotective effects against H₂O₂-induced cardiomyocytes injury, and compound 5 showed statistically significant cardioprotective effect in vitro assays.