The use of plants in the traditional management of diabetes in Nigeria: Pharmacological and toxicological considerations

Ethnopharmacological relevance: 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. Materials and 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. Conclusion: 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

Response of soil multifractal characteristics and erodibility to 15-year fertilization on cropland in the Loess Plateau, China

Understanding the influence of long-term fertilization on the multifractal characteristics and erodibility of soil of cultivated land on the Loess Plateau of China could help prevent soil erosion and promote the sustainable development of agriculture. We collected 27 soil samples from 0 to20cm layers of nine fertilizer treatments. Renyi spectrum (D-q) and singularity spectrum (integral()) were applied to characterize soil particle-size distribution (PSD). The multifractal parameters of capacity dimension (D-0), entropy dimension (D-1), Holder exponent of order zero ((0)), and erodibility K and anti-erodibility indices (aggregate state and degree) were used to determine the effect of fertilization on soil properties and erodibility. The multifractal models could characterize the PSDs in the various fertilizer treatments well. Treatments receiving manure had higher D-0, D-1, (0), soil organic carbon (SOC) content, aggregate state and degree and lower erodibility. It was concluded that D-0, D-1, and (0) could clearly discriminate among the various treatments, and the combined application of mineral fertilizers and organic manure greatly improved soil quality and structure of the cultivated land in the Loess Plateau. Furthermore, changes of multifractal parameters D-0, D-1, and (0), especially D-1, was mainly due to the reduced soil erosion and the increase of SOC