In vitro anti-inflammatory properties of fermented pepino (Solanum muricatum) milk by γ-aminobutyric acid-producing Lactobacillus brevis and an in vivo animal model for evaluating its effects on hypertension

BACKGROUND: The objectives of this study were to determine the in vitro anti-inflammatory and in vivo antihypertensive effects of fermented pepino (Solanum muricatum) milk by Lactobacillus brevis with the goal of developing functional healthy products. The inflammatory factors of fermented pepino milk with L. brevis were assessed in RAW 264.7 macrophages, including nitric oxide (NO) production. Inflammatory factor genes of cyclooxygenase (COX)-1 and -2, and tumor necrosis factor (TNF)-α were also assayed by a reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Results showed that fermented PE inhibited NO production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells with 150 mg mL^-1 fermented PE completely blocking LPS-induced NO production. The mRNA expressions of COX-1, COX-2, and iNOS were attenuated by treatment with higher concentrations of fermented PE (150 mg/ml). Cells treated with fermented pepino extract (PE) (100 ng mL^-1) exhibited strikingly decreased LPS-induced expression of TNF-α mRNA. During the feeding trial, rats treated with 10% fermented pepino milk (100 μg 2.5 mL^-1) and 100% fermented pepino milk (1000 μg 2.5 mL^-1) exhibited significant decreases in the systolic blood pressure. CONCLUSION: Our results showed that fermented pepino milk has wide potential applications for development as a health food.