title: Butanol fraction of Parkia biglobosa (Jacq.) G. Don leaves enhance pancreatic β-cell functions, stimulates insulin secretion and ameliorates other type 2 diabetes-associated complications in rats.
abstract: BACKGROUND
  Ethnopharmacological surveys have reported that Parkia biglobosa (Jacq.) G. Don (Leguminosae) is among the plants commonly used in the traditional management of diabetes mellitus in Nigeria and Togo.
  
  
  OBJECTIVE
  This study investigated the anti-diabetic activity of the butanol fraction of P. biglobosa leaves (PBBF) in a type 2 diabetes (T2D) model of rats and a possible bioactive compound in the fraction.
  
  
  METHODS
  T2D was induced by feeding rats with a 10% fructose solution ad libitum for two weeks followed by an intraperitoneal injection of 40mg/kg body weight streptozotocin and the animals were orally treated with 150 and 300mg/kg BW of the PBBF for five days in a week. Another group of rats was non-diabetic but similarly administered with 300mg/kg BW of the PBBF. Food and fluid intakes, body weight changes and blood glucose levels were monitored during the experiment while other relevant diabetes-associated parameters were measured at the end of the experiment.
  
  
  RESULTS
  The PBBF treatments significantly (P<0.05) decreased the blood glucose levels and improved the glucose tolerance ability compared to untreated diabetic rats. Furthermore, the treatments were found to improve pancreatic β cell function (HOMA-β), stimulate insulin secretions, decrease insulin resistance (HOMA-IR), restore liver glycogen, ameliorate serum dyslipidaemia and prevent hepatic and renal damages compared to untreated diabetic rats. Phytochemical analysis of the fraction led to the isolation of lupeol which inhibited α-glucosidase and α-amylase in non-competitive and uncompetitive inhibition patterns respectively.
  
  
  CONCLUSIONS
  It was concluded that PBBF possessed remarkable anti-T2D activity which is mediated through modulation of β-cell function and stimulation of insulin secretion and the lower dose (150mg/kg BW) was found optimum for anti-T2D activity compared to the high dose (300mg/kg BW) in this study.
authors.affiliation: School of Life Sciences, University of KwaZulu-Natal (Westville Campus), Durban 4000 South Africa; Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria.
authors.forename: Mohammed Auwal
authors.initials: MA
authors.lastname: Ibrahim
authors.affiliation: School of Chemistry, University of KwaZulu-Natal (Westville Campus), Durban 4000 South Africa.
authors.forename: James Dama
authors.initials: JD
authors.lastname: Habila
authors.affiliation: School of Chemistry, University of KwaZulu-Natal (Westville Campus), Durban 4000 South Africa.
authors.forename: Neil Anthony
authors.initials: NA
authors.lastname: Koorbanally
authors.affiliation: School of Life Sciences, University of KwaZulu-Natal (Westville Campus), Durban 4000 South Africa. Electronic address: islamd@ukzn.ac.za.
authors.forename: Md Shahidul
authors.initials: MS
authors.lastname: Islam
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D000440:Butanols / Q000737:chemistry; D048909:Diabetes Complications / Q000188:drug therapy* / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism*; D050171:Dyslipidemias / Q000378:metabolism; D007887:Fabaceae / Q000737:chemistry*; D005951:Glucose Tolerance Test / Q000379:methods; D007004:Hypoglycemic Agents / Q000737:chemistry / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism*; D007333:Insulin Resistance / Q000502:physiology; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000378:metabolism; D008112:Liver Glycogen / Q000378:metabolism; D008297:Male; D009549:Nigeria; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014037:Togo; D000516:alpha-Amylases / Q000378:metabolism; D000520:alpha-Glucosidases / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D000440:Butanols; D007004:Hypoglycemic Agents; D007328:Insulin; D008112:Liver Glycogen; D010936:Plant Extracts; D000516:alpha-Amylases; D000520:alpha-Glucosidases
keywords: African locust bean; Insulin; Lupeol; Parkia biglobosa; Rats; Type 2 diabetes