title: The use of plants in the traditional management of diabetes in Nigeria: pharmacological and toxicological considerations.
abstract: BACKGROUND
  The prevalence of diabetes is on a steady increase worldwide and it is now identified as one of the main threats to human health in the 21st century. In Nigeria, the use of herbal medicine alone or alongside prescription drugs for its management is quite common. We hereby carry out a review of medicinal plants traditionally used for diabetes management in Nigeria. Based on the available evidence on the species׳ pharmacology and safety, we highlight ways in which their therapeutic potential can be properly harnessed for possible integration into the country׳s healthcare system.
  
  
  METHODS
  Ethnobotanical information was obtained from a literature search of electronic databases such as Google Scholar, Pubmed and Scopus up to 2013 for publications on medicinal plants used in diabetes management, in which the place of use and/or sample collection was identified as Nigeria. 'Diabetes' and 'Nigeria' were used as keywords for the primary searches; and then 'Plant name - accepted or synonyms', 'Constituents', 'Drug interaction' and/or 'Toxicity' for the secondary searches.
  
  
  RESULTS
  The hypoglycemic effect of over a hundred out of the 115 plants reviewed in this paper is backed by preclinical experimental evidence, either in vivo or in vitro. One-third of the plants have been studied for their mechanism of action, while isolation of the bioactive constituent(s) has been accomplished for twenty three plants. Some plants showed specific organ toxicity, mostly nephrotoxic or hepatotoxic, with direct effects on the levels of some liver function enzymes. Twenty eight plants have been identified as in vitro modulators of P-glycoprotein and/or one or more of the cytochrome P450 enzymes, while eleven plants altered the levels of phase 2 metabolic enzymes, chiefly glutathione, with the potential to alter the pharmacokinetics of co-administered drugs.
  
  
  CONCLUSIONS
  This review, therefore, provides a useful resource to enable a thorough assessment of the profile of plants used in diabetes management so as to ensure a more rational use. By anticipating potential toxicities or possible herb-drug interactions, significant risks which would otherwise represent a burden on the country׳s healthcare system can be avoided.
authors.affiliation: Center for Pharmacognosy and Phytotherapy, Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University College London, 29-39 Brunswick Square, WC1N 1AX London, United Kingdom. Electronic address: amaka.ezuruike@gmail.com.
authors.forename: Udoamaka F
authors.initials: UF
authors.lastname: Ezuruike
authors.affiliation: Center for Pharmacognosy and Phytotherapy, Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University College London, 29-39 Brunswick Square, WC1N 1AX London, United Kingdom. Electronic address: j.prieto@ucl.ac.uk.
authors.forename: Jose M
authors.initials: JM
authors.lastname: Prieto
mesh_terms: D000818:Animals; D003920:Diabetes Mellitus / Q000188:drug therapy*; D020834:Ethnopharmacology; D041743:Herb-Drug Interactions; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D016488:Medicine, African Traditional; D009549:Nigeria; D008517:Phytotherapy / Q000009:adverse effects / Q000379:methods; D028321:Plant Preparations / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D010946:Plants, Medicinal / Q000737:chemistry*
chemical_list: D007004:Hypoglycemic Agents; D028321:Plant Preparations
keywords: Diabetes; Ethnopharmacology; Herb–drug interactions; Nigeria; WHO Traditional Medicine Strategy