Daily Ingestion of Eggplant Powder Improves Blood Pressure and Psychological State in Stressed Individuals: A Randomized Placebo-Controlled Study.

Eggplant (Solanum melongena) is a globally popular vegetable and its significant health effect has not been reported in randomized controlled trials. Recently, we reported that eggplant was rich in choline esters, including acetylcholine (ACh), and had an antihypertensive effect in spontaneously hypertensive rats. Here, we evaluated the effects of a continuous intake of eggplant powder on blood pressure (BP), stress, and psychological state (PS) in 100 stressed participants with normal-high BP or grade 1 hypertension in a randomized, double-blind, placebo-controlled, parallel-group comparative study. The participants were randomly assigned to the eggplant or placebo group. Participants in the eggplant group ingested capsules containing eggplant powder (1.2 g/day; 2.3 mg of ACh/day) for 12 weeks, whereas participants in the placebo group ingested placebo capsules. The primary outcome assessed was hospital BP. Secondary outcomes were stress and PS. Eggplant powder intake significantly decreased the hospital diastolic blood pressure (DBP) at week 8 overall and in the normal-high BP group, and the systolic blood pressure (SBP) and DBP at week 12 overall and in the grade 1 hypertension group, compared to those of the placebo group. It also improved negative PSs at week 8 or 12 in the normal-high BP group. This is the first evidence of the BP- and PS-improving effects of eggplant intake in humans. The functional substance responsible for the effects was estimated to be eggplant-derived choline ester, namely ACh.

Effects of the Chemical Structures of Oligoarginines Conjugated to Biocompatible Polymers as a Mucosal Adjuvant on Antibody Induction in Nasal Cavities.

We have been investigating the potential of oligoarginine-linked polymers as an adjuvant for mucosal vaccination that induces immunoglobulin G (IgG) in systemic circulation and immunoglobulin A (IgA) secreted on the mucosa. Our latest infection experiments demonstrated that mice immunized nasally with a mixture of inactivated influenza viruses and poly(N-vinylacetamide-co-acrylic acid) (PNVA-co-AA) modified with D-octaarginine were perfectly protected from homologous virus infection. On the contrary, virus infection was observed in mice immunized with the antigen alone. This difference was presumably due to insignificant induction of secreted IgA on the nasal mucosa in the latter mice. Since it was unclear whether the current induction level was sufficient for heterologous virus infection, we evaluated the effects of the chemical structures of oligoarginines conjugated to PNVA-co-AA on induction of intranasal IgA. The number and optical activity of the arginine residues and the degree of modification with oligoarginines in the polymer backbone were listed as a factor that would influence IgA induction. Mouse experiments revealed that maximization of the modification resulted in an increase in adjuvant activities of oligoarginine-linked polymers most effectively. Glycine segments inserted between oligoarginines and the polymer backbone were a prerequisite for the maximization. The highest IgA level was observed when antigens were coadministered with diglycine-D-octaarginine-linked PNVA-co-AA.