Potential Use of 3D CORAGRAF-Loaded PDGF-BB in PLGA Microsphere Seeded Mesenchymal Stromal Cells in Enhancing the Repair of Calvaria Critical-Size Bone Defect in Rat Model.

Our previous study evidenced that the 3D CORAGRAF loaded with PLGA microsphere constitutes PDGF-BB can support cell attachment and proliferation and can induce an osteogenic commitment of mesenchymal stromal cells in the in vitro condition. However, how this construct can perform in pathophysiological conditions in terms of repairing critical bone defects is yet to be understood. A study was therefore conducted to investigate the regeneration potential of calvaria critical-size defects using CORAGRAF + PLGA with PDGF-BB + mesenchymal stromal cells (MSCs) in a rat model. A 5 mm critical bone defect was created on calvaria of 40 male Sprague-Dawley rats. CORAGRAF incorporated either with or without PDGF-BB and seeded with rat bone-marrow-derived MSCs was implanted at the defect region. The bone regeneration potential of implanted constructs was assessed using micro-CT imaging and histological staining in weeks 4 and 8. The micro-CT images indicated a significant closure of defects in the cranial bone of the rats treated with 3D CORAGRAF + PLGA with PDGF-BB + MSCs on week 4 and 8 post-implantation. This finding, further supported with the histology outcome where the rat cranial defect treated with CORAGRAF + PLGA with PDGF-BB + MSCs indicated neo-bony ingrowth with organized and mature bone-like morphology as compared with other groups. The previous in vitro results substantiated with our pre-clinical findings demonstrate that the combination of CORAGRAF + PLGA with PDGF-BB + MSCs could be an ideal construct to support bone regeneration in critical bone defects. Hence, this construct can be further investigated for its safety and efficacy in large animal models, or it can be skipped to human trial prior for commercialization.

Effect of Pithecellobium dulce (Roxb.) Benth. fruit extract on cysteamine induced duodenal ulcer in rats.

The edible fruits of Pithecellobium dulce (Roxb.) Benth. are traditionally used for various gastric complications in India. Here, we investigated the antiulcer activity of hydroalcoholic fruit extract of P. dulce (HAEPD) by applying cysteamine induced duodenal ulcer model in rats. Duodenal ulcer was induced in male albino Wistar rats by oral administration of cysteamine @ 420 mg/kg body wt. as a single dose. The rats were pre-administered orally with HAEPD @ 200 mg/kg body wt. for 30 days prior to ulcer induction. Rats pre-administered with ranitidine @ 30 mg/kg body wt. served as reference drug control. Ulcer score, thiobarbituric acid reactive substances (TBARS), glycoproteins, superoxide dismutase, catalase and glutathione peroxidase and reduced glutathione levels were measured in the duodenum. Rats pre-administered with the HAEPD showed significantly reduced ulcer score comparable to that of ranitidine pretreated rats. The co-administration of HAEPD lowered the TBARS level and also restored the levels of glycoproteins, enzymatic and non-enzymatic antioxidants. Histopathological observations confirmed the presence of inflammation, necrosis and hemorrhagic spots in the duodenum of ulcer control rats which were significantly reduced due to HAEPD treatment. No abnormal alterations were observed in normal rats treated with HAEPD at the dosage studied. The results demonstrated antioxidant and cytoprotective nature of P. dulce, and thereby its significant anti ulcer property.

Antiulcerogenic activity of hydroalcoholic fruit extract of Pithecellobium dulce in different experimental ulcer models in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: The ethnopharmacological importance of Pithecellobium dulce is evidenced by its traditional use for gastric complications. The aim of the study is to evaluate the gastroprotective activity and the mechanism of action of hydroalcoholic fruit extract of P. dulce (HAEPD) in rats by using chemical and stress induced ulcer models. MATERIALS AND METHODS: Gastric ulcer was induced by administering alcohol (or) acetylsalicylic acid (or) hypothermic restraint stress to rats pretreated with HAEPD (200 mg/kgbwt for 30 day). Volume of gastric fluid, pH, acidity, activities of pepsin, H(+), K(+)-ATPase, myeloperoxidase, mucin content, nucleic acids, glycoproteins and prostaglandin E(2) (PGE(2)) levels were assessed in gastric tissues. RESULTS: Ulcer score was significantly minimized in HAEPD administered animals. pH and acidity of gastric fluid were significantly minimized and the mucin, PGE(2) levels were significantly maintained in drug pre administered animals. The activities of H(+), K(+)- ATPase and myeloperoxidase were found to be significantly elevated in ulcer control animals and found to be decreased in drug pretreated animals. The cell proliferation was found to be enhanced in drug received animals. The total protein bound carbohydrate to total protein ratio was found to be significantly maintained by HAEPD. The effects were found to be comparable with that of standard drug omeprazole. CONCLUSION: It is concluded that HAEPD possess a potent antiulcer activity probably by acting as cytoprotective and antiacid secretory agent.

Acute and sub-acute toxicity study of hydroalcoholic fruit extract of Pithecellobium dulce.

This study was carried out to evaluate the acute and sub-acute toxicity profile of the hydroalcoholic fruit extract (HAEPD) of Pithecellobium dulce (Leguminosae). Albino rats were treated orally with 100, 200 and 500 mg kg(-1) bodyweight (BW) of HAEPD for 90 days to assess its sub-acute toxicity. HAEPD at single doses of 100, 500, 1000, 2000 and 4000 mg kg(-1) BW was also administered to rats to assess its acute toxicity. The rats were observed for physical discomfort, BW change and feeding habits. Pithecellobium dulce did not cause any abnormal changes in haematological or biochemical parameters. Pathologically, no gross abnormality in the tissue architecture was observed. The LD(50) was found to be 3916 mg kg(-1) BW and potential effective doses for efficacy studies are 100 and 300 mg kg(-1) BW as the minimum and maximum doses, respectively. It is concluded that HAEPD can be used safely for experimental and clinical trials.

Effect of Pithecellobium dulce (Roxb.) Benth. fruit extract on cysteamine induced duodenal ulcer in rats.

The edible fruits of Pithecellobium dulce (Roxb.) Benth. are traditionally used for various gastric complications in India. Here, we investigated the antiulcer activity of hydroalcoholic fruit extract of P. dulce (HAEPD) by applying cysteamine induced duodenal ulcer model in rats. Duodenal ulcer was induced in male albino Wistar rats by oral administration of cysteamine @ 420 mg/kg body wt. as a single dose. The rats were pre-administered orally with HAEPD @ 200 mg/kg body wt. for 30 days prior to ulcer induction. Rats pre-administered with ranitidine @ 30 mg/kg body wt. served as reference drug control. Ulcer score, thiobarbituric acid reactive substances (TBARS), glycoproteins, superoxide dismutase, catalase and glutathione peroxidase and reduced glutathione levels were measured in the duodenum. Rats pre-administered with the HAEPD showed significantly reduced ulcer score comparable to that of ranitidine pretreated rats. The co-administration of HAEPD lowered the TBARS level and also restored the levels of glycoproteins, enzymatic and non-enzymatic antioxidants. Histopathological observations confirmed the presence of inflammation, necrosis and hemorrhagic spots in the duodenum of ulcer control rats which were significantly reduced due to HAEPD treatment. No abnormal alterations were observed in normal rats treated with HAEPD at the dosage studied. The results demonstrated antioxidant and cytoprotective nature of P. dulce, and thereby its significant anti ulcer property.