Influence Of Sickle Heterozygous Status And Glucose-6-phosphate Dehydrogenase Deficiency On The Clinico-haematolgoical Profile Of Plasmodium Falciparum -infected Children

Sickle haemoglobin (HbS) and glucose-6-phosphate dehydrogenase (G6PD) enzyme deficiency genes are known to offer reliable protection against falciparum malaria in malaria endemic areas of the world. However, the mechanism of protection is not yet completely understood. In this study, we investigated the contribution of HbS and G6PD enzyme deficiency status in ameliorating the severity of malaria attack by comparing the clinical symptoms, parasitaemia and haematological profiles of Plasmodium falciparum -infected volunteer children. The selected group of children, G6PD deficient sickle heterozygotes (HbAS) (n = 5), G6PD non-deficient HbAS (n = 30), G6PD deficient dominant homozygotes (HbAA) (n = 10) and G6PD non-deficient HbAA (n = 30) were monitored for a period of one year with a view to elucidating further the involvement of HbS and G6PD enzyme deficiency in the protection of children against plasmodial infection. Results revealed greater severity (indicated by malarial anaemia), higher incidence of atypical thrombocytopenia, high white blood cell (WBC) counts and significantly higher (P < 0.05) parasite density and percentage parasitaemia in G6PD non-deficient HbAA subjects compared to G6PD non-deficient HbAS, G6PD deficient HbAS subject and G6PD deficient HbAA. Less severe clinical malarial symptoms were also observed more in G6PD deficient HbAS when compared to G6PD non-deficient HbAA subjects during malaria attack. These results seem to indicate that inheriting both genetic defects reduces the profligacy of malaria parasite and hence, ameliorate the severity of acute falciparum malaria. Consequently, selective advantage against fatal falciparum malaria seems to be conferred since malarial anaemia, parasitaemia and severe malarial symptoms were significantly reduced

Sphingomyelinase inhibitory and free radical scavenging potential of selected Nigerian medicinal plant extracts

Ceramides from sphingolipid breakdown, and other sphingolipid metabolites, mediate cellular signalling in infectious and other diseases. Therefore, inhibitors of sphingomyelinases (SMases), hold promise as prospective therapeutic agents. Considering the potential therapeutic utility, this in vitro study explored the sphingomyelinase inhibitory, and free radical scavenging potential of five Nigerian medicinal plant leaf extracts, purported to have efficacy against diseases, including HIV/AIDS. The extracts\u2019 sphingomyelinase inhibitory potencies were assessed colorimetrically and theirfree radical scavenging capabilities were assayed by the ability to quench 2,2\u2010diphenyl\u20101\u2010picrylhydrazyl (DPPH) radical and superoxide anion (O2.\u2010) radical. Considering their IC50 (\u3bcg/ml) values, the extracts inhibited the biochemical activity of sphingomyelinase in a dose-dependent manner, relative to imipramine the standard inhibitor (IC50 38.5 \ub1 2.4 \u3bcg/ml). With Aloe vera as least inhibitory, inhibition increased as follows: Aloe vera (Asphodelaceae) (1132 \ub1 10.8) < Senna siamea (Fabaceae) (992.2 \ub1 11.2) < Azadirachta indica (Meliaceae) (984 \ub1 7.4) < Landolphia owariensis (Apocynaceae) (146.3 \ub1 9.4) < Stachytarpheta angustifolia (Verbenacae) (100.3 \ub1 8.7). DPPH radical scavenging relative to ascorbic acid standard increased as: A. indica < A. vera < S. siamea < S. angustifolia < L. owariensis; and superoxide anion quenching, relative to standard rutin increased as: A. vera < S. angustifolia < L. owariensis < S. siamea < A. indica.These results showed thatthe most potent SMase inhibitor was S. angustifolia; whereas, for DPPH radical scavenging and superoxide inhibition, the most potent of the five extracts were L. owariensis and A. indica respectively.These extracts deserve further investigation into their biological effects

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

Influence Of Sickle Heterozygous Status And Glucose-6-phosphate Dehydrogenase Deficiency On The Clinico-haematolgoical Profile Of Plasmodium Falciparum -infected Children

Sickle haemoglobin (HbS) and glucose-6-phosphate dehydrogenase (G6PD) enzyme deficiency genes are known to offer reliable protection against falciparum malaria in malaria endemic areas of the world. However, the mechanism of protection is not yet completely understood. In this study, we investigated the contribution of HbS and G6PD enzyme deficiency status in ameliorating the severity of malaria attack by comparing the clinical symptoms, parasitaemia and haematological profiles of Plasmodium falciparum -infected volunteer children. The selected group of children, G6PD deficient sickle heterozygotes (HbAS) (n = 5), G6PD non-deficient HbAS (n = 30), G6PD deficient dominant homozygotes (HbAA) (n = 10) and G6PD non-deficient HbAA (n = 30) were monitored for a period of one year with a view to elucidating further the involvement of HbS and G6PD enzyme deficiency in the protection of children against plasmodial infection. Results revealed greater severity (indicated by malarial anaemia), higher incidence of atypical thrombocytopenia, high white blood cell (WBC) counts and significantly higher (P < 0.05) parasite density and percentage parasitaemia in G6PD non-deficient HbAA subjects compared to G6PD non-deficient HbAS, G6PD deficient HbAS subject and G6PD deficient HbAA. Less severe clinical malarial symptoms were also observed more in G6PD deficient HbAS when compared to G6PD non-deficient HbAA subjects during malaria attack. These results seem to indicate that inheriting both genetic defects reduces the profligacy of malaria parasite and hence, ameliorate the severity of acute falciparum malaria. Consequently, selective advantage against fatal falciparum malaria seems to be conferred since malarial anaemia, parasitaemia and severe malarial symptoms were significantly reduced

Lignans and Stilbenes from African Medicinal Plants

Lignans and stilbenes are two groups of related secondary metabolites widely distributed in the plant kingdom. They have been found in roots, rhizomes, stems, bark, leaves, seeds, and fruits of more than 100 species of African medical plants belonging to various families. Lignans are biosynthesized by oxidative dimerization of two phenylpropanoid units; they possess an enormous structural diversity originating from various linkage patterns. Stilbenes are also biosynthesized from phenylpropanoids that can be further oxidized to form oligomers. Both lignans and stilbenes from African medicinal plants have attracted intense interest because of their structural diversity and biological functions, specifically for their anticancer, antiplasmodial, and antibacterial properties. This is exemplified by many clinical studies that have been performed on the use of schweinfurthins, combretastatins, and steganolides to treat cancer. This chapter provides information on the biosynthesis, subclasses, and structural diversity of lignans and stilbenes, as well as their biological activity. Selected data are presented for those molecules with biological information

Sphingomyelinase inhibitory and free radical scavenging potential of selected Nigerian medicinal plant extracts

Ceramides from sphingolipid breakdown, and other sphingolipid metabolites, mediate cellular signalling in infectious and other diseases. Therefore, inhibitors of sphingomyelinases (SMases), hold promise as prospective therapeutic agents. Considering the potential therapeutic utility, this in vitro study explored the sphingomyelinase inhibitory, and free radical scavenging potential of five Nigerian medicinal plant leaf extracts, purported to have efficacy against diseases, including HIV/AIDS. The extracts’ sphingomyelinase inhibitory potencies were assessed colorimetrically and theirfree radical scavenging capabilities were assayed by the ability to quench 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical and superoxide anion (O2.‐) radical. Considering their IC50 (μg/ml) values, the extracts inhibited the biochemical activity of sphingomyelinase in a dose-dependent manner, relative to imipramine the standard inhibitor (IC50 38.5 ± 2.4 μg/ml). With Aloe vera as least inhibitory, inhibition increased as follows: Aloe vera (Asphodelaceae) (1132 ± 10.8) < Senna siamea (Fabaceae) (992.2 ± 11.2) < Azadirachta indica (Meliaceae) (984 ± 7.4) < Landolphia owariensis (Apocynaceae) (146.3 ± 9.4) < Stachytarpheta angustifolia (Verbenacae) (100.3 ± 8.7). DPPH radical scavenging relative to ascorbic acid standard increased as: A. indica < A. vera < S. siamea < S. angustifolia < L. owariensis; and superoxide anion quenching, relative to standard rutin increased as: A. vera < S. angustifolia < L. owariensis < S. siamea < A. indica.These results showed thatthe most potent SMase inhibitor was S. angustifolia; whereas, for DPPH radical scavenging and superoxide inhibition, the most potent of the five extracts were L. owariensis and A. indica respectively.These extracts deserve further investigation into their biological effects