ABSTRACT
ETHNO-PHARMACOLOGICAL RELEVANCE: The genus Aloe has a long history of usage in medicine. Aloe barbadensis Miller, commonly known as Aloe vera, is said to possess anti-diabetic, anti-inflammatory, anti-cancer, anti-microbial, immunomodulation, wound healing properties. AIM OF THE STUDY: In diabetes mellitus, loss in intestinal permeability is observed with high levels of zonulin and low levels of glucagon-like peptide-1 (GLP-1) leading to hyperglycemia. The aim of the study was to understand the role of peptide/polypeptide fraction (PPF) of Aloe vera in the alleviation of diabetes through maintaining the intestinal permeability by regulating the zonulin and GLP-1 levels. MATERIALS AND METHODS: The PPF of Aloe vera was obtained through trichloroacetic acid precipitation. The anti-diabetic potential of the PPF was tested through DPP-IV inhibition, glucose diffusion assay, and by using Rin-m5F cells. The anti-diabetic potential of the PPF was tested at a dose of 0.450 mg/kg bw in vivo using streptozotocin-induced diabetic Wistar rats. The effect of PPF on fasting plasma glucose, insulin, glucagon, Zonulin, GLP-1, DPP-IV, levels were studied in diabetic rats. The histopathological studies of the pancreas, small intestine, and liver were carried out for organ-specific effects. RESULTS: PPF has the ability to reduce fasting plasma glucose levels with concomitant increase in insulin levels in streptozotocin-induced diabetic rats. It was also observed that increase in GLP-1 levels with a decrease in DPP-IV and zonulin levels thereby mitigating the loss of intestinal permeability. These findings correlate with the small intestine's histopathological observation where the excessive proliferation of epithelium in the small intestine of diabetic rats was reduced after PPF treatment. CONCLUSION: These results suggest that the PPF of Aloe vera alleviates diabetes through islet cell rejuvenation via GLP-1/DPP-IV pathway and thereby suggesting the usage of PPF as an alternate medicine for diabetes mellitus with the possibility to reduce the intestinal permeability and zonulin levels.
Subject(s)
Aloe/chemistry , Diabetes Mellitus, Experimental/drug therapy , Dipeptidyl Peptidase 4/metabolism , Glucagon-Like Peptide 1/metabolism , Haptoglobins/metabolism , Hypoglycemic Agents/pharmacology , Plant Extracts/pharmacology , Protein Precursors/metabolism , Animals , Blood Glucose/drug effects , Cell Survival/drug effects , Cytokines/metabolism , Glucagon/blood , Glucose-6-Phosphate/metabolism , Glycogen/metabolism , Hexokinase/metabolism , Hypoglycemic Agents/therapeutic use , Inflammation/metabolism , Insulin/blood , Intestine, Small/pathology , Liver/pathology , Nitric Oxide/metabolism , Pancreas/pathology , Plant Extracts/therapeutic use , Rats, Wistar , StreptozocinABSTRACT
Objective: To evaluate the anti-inflammatory potential of peptide/polypeptide fraction of Aloe vera through in vitro and in vivo studies. Methods: The peptide/polypeptide fraction from Aloe vera was obtained through trichloroacetic acid precipitation. The anti-inflammatory property of the peptide/polypeptide fraction was tested by protein denaturation, membrane stabilization assays. The effect of the fraction on RAW 264.7 cell viability was examined by MTT assays. The nitric oxide level was determined through Griess reagent. TNF-α and IL-6 levels were estimated using ELISA kits. In vivo studies were carried out in male Wistar rats through injection of Freund's adjuvant in the hind paw. Paw edema was measured through the Vernier scale and levels of alanine aminotransferase, aspartate transaminase, TNF-α, IL-6, and secretory phospholipase A2 were estimated through their respective kits after fourteen days of treatment. GraphPad Prism6 was used for analyzing the results. Results: The peptide/polypeptide extract inhibited protein denaturation with an IC50 value of (218.9±15.6) μg/mL and stabilized the membrane of red blood cells with an IC50 value of (275.9±19.1) μg/mL. The extract showed no changes in cell morphology or cytotoxicity up to the concentration of 20 μg/mL in MTT assays. The peptide/polypeptide fraction markedly reduced the levels of proinflammatory markers and mediators in both in vitro and in vivo studies. Conclusions: The results indicate that the peptide/polypeptide fraction of Aloe vera has antiinflammatory property through inhibition of inflammatory markers and mediators responsible for NF-κB and mitogen-activated protein kinase pathways.
ABSTRACT
Objective: To evaluate the anti-inflammatory potential of peptide/polypeptide fraction of Aloe vera through in vitro and in vivo studies. Methods: The peptide/polypeptide fraction from Aloe vera was obtained through trichloroacetic acid precipitation. The anti-inflammatory property of the peptide/polypeptide fraction was tested by protein denaturation, membrane stabilization assays. The effect of the fraction on RAW 264.7 cell viability was examined by MTT assays. The nitric oxide level was determined through Griess reagent. TNF-α and IL-6 levels were estimated using ELISA kits. In vivo studies were carried out in male Wistar rats through injection of Freund's adjuvant in the hind paw. Paw edema was measured through the Vernier scale and levels of alanine aminotransferase, aspartate transaminase, TNF-α, IL-6, and secretory phospholipase A2 were estimated through their respective kits after fourteen days of treatment. GraphPad Prism6 was used for analyzing the results. Results: The peptide/polypeptide extract inhibited protein denaturation with an IC
