Repeated 28-Day Oral Toxicological Study and Gastroprotective Effects of Nigella sativa L. Oil (Shuhada) against Ethanol-Induced Gastric Mucosal Injury in Rats.

Nigella sativa L. and black seeds are traditionally used for cooking and medicinal purposes in Arab and other countries. Although N. sativa seed extract has many known biological effects, the biological effects of cold-pressed N. sativa oil are poorly understood. Therefore, the objective of this study was to investigate the gastroprotective effects and subacute oral toxicity of black seed oil (BSO) in an animal model. The gastroprotective effects of oral BSO (50% and 100%; 1 mg/kg) were tested using acute experimental models of ethanol-induced gastric ulcers. Gross and histological gastric lesions, ulcerated gastric areas, ulcer index score, percentage of inhibition rate, gastric juice pH, and gastric wall mucus were all evaluated. The subacute toxicity of BSO and its thymoquinone (TQ) content were also examined. The results indicated that the administration of BSO exerted gastroprotective effects by increasing the gastric wall mucus and decreasing gastric juice acidity. In the subacute toxicity test, the animals behaved normally, and their weight and water and food intake did not show significant variations. High-performance liquid chromatography detected 7.3 mg/mL TQ in BSO. These findings suggest that BSO may be a safe therapeutic drug for preventing gastric ulcers.

Recombinant Human Dentin Matrix Protein 1 (hDMP1) Expressed in Nicotiana benthamiana Potentially Induces Osteogenic Differentiation.

Inductive molecules are critical components for successful bone tissue engineering. Dentin matrix protein-1 (DMP1), a non-collagenous protein in the bone matrix, has been shown to play roles in osteogenic differentiation and phosphate homeostasis. This study aimed to produce recombinant human dentin matrix protein-1 (hDMP1) in Nicotiana benthamiana and investigated the ability of this plant-produced DMP1 to induce osteogenesis in human periodontal ligament stem cells (hPDLSCs). The hDMP1 gene was cloned into the geminiviral vector for transient expression in N. benthamiana. We found that hDMP1 was transiently expressed in N. benthamiana leaves and could be purified by ammonium sulphate precipitation followed by nickel affinity chromatography. The effects of hDMP1 on the induction of cell proliferation and osteogenic differentiation were investigated. The results indicated that plant-produced hDMP1 could induce the cell proliferation of hPDLSCs and increase the expression levels of osteogenic genes, including osterix (OSX), type I collagen (COL1), bone morphogenetic protein-2 (BMP2), and Wnt3a. Moreover, the plant-produced hDMP1 promoted calcium deposition in hPDLSCs as determined by alizarin red S staining. In conclusion, our results indicated that plant-produced hDMP1 could induce osteogenic differentiation in hPDLSCs and could potentially be used as a bone inducer in bone tissue engineering.