Abstract

Artesunate (AS) is a class of medication known as artemesinin used in the treatment of

malaria. The occurrence ofPlasmodium falciparum malaria during pregnancy exposes the

mother and foetus to serious risks. The present study was aimed at evaluating the effect of

artesunate during pregnancy with particular reference to the histology and neurochemistry

of the cerebrum and hippocampus. Thirty pregnant Wistar rats were divided into three

groups and were treated intragastrically on gestation day 9 to 15 with safe or high dose

regimen of 4mg/kg/3days + 2mg/kg/4days or 10mg/kg/3days + 4mg/kg/4 days respectively.

Control rats were treated with distilled water. Five pups were sacrificed at each time

intervals of gestation day (GD) 20, postnatal days (PD) 1, 4, 7, 14, 21, and 28 for

morphometrical, histological and immunohistochemical studies on the cerebrum and

hippocampus. The brain tissues were dissected, fixed, processed and examined by light

microscope. Morphometrically, safe dose showed significantly stunted growth of body

particularly in the limbs, tails and brain compared to control. High dose induced marked

teratogenic effects characterized by severe embryo loss indicated as resorptions in most

dams. However, in the dams that littered there was high incidence of craniofacial and other

skeletal malformation. Histologically, the safe dose showed decrease in cell proliferation

with marked difference in the layer stratification of the cerebrum and neuronal degeneration

characterized by pyknosis, vacuolation, and degeneration of the pyramidal cells compared

to the control. High dose showed complete retardation of cerebral and hippocampal

development in the few pups. It also showed a severe form of neurodegeneration

characterize by cytoplasmic vacuolations, distortion of the pyramidal cell layers, central

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CHAPTER ONE

1.0 INTRODUCTION

1.1 Background

Malaria remains one of the world‟s most significant health problems despite necessary

research and control efforts (WHO, 2008). It has continued to be the most devastating

human parasitic infection in the world, with about (100 million in Nigeria) at risk of

infection (Giles, 1997). It is said to be responsible for over 2 million deaths each year, and

a leading cause of death in children in those countries where the disease is endemic. This

disease is widespread in tropical and sub-tropical regions (WHO 2010 and Adebisi, 2010).

According to the World Malaria Report, 109 countries were endemic for malaria in 2008,

malaria infects between 350 and 500 million people each year, and kills one million (WHO

2006b; 2008). The occurrence of malaria during pregnancy exposes the mother and infants

to serious risks (WHO, 2010) as pregnancy decreases a woman‟s immunity to malaria,

making her more vulnerable to malaria infection and increasing the possibility of illness,

severe anaemia and death of the mother (WHO, 2010). Regarding the unborn child,

maternal malaria increases the risk of unplanned abortion, stillbirth, premature delivery low

birth weight, infant mortality which is a leading cause of child mortality (WHO, 2003;

2009a, 2010).

Every year at least 30 million pregnancies occur among women in malaria-endemic areas

of Africa. Malaria during pregnancy causes up to 10 000 maternal deaths and 200 000 new

born deaths each year (WHO 2003; WHO 2009a). Artesunate safety during the first

trimester (week 1-12) has not yet been proven (WHO, 2006c). It is therefore imperative that

1

pregnant women be protected against malaria, and the pregnant woman with malaria

receives treatment as soon as possible (WHO, 2002a; 2009a).

Over 40% of the world population lives in endemic areas estimated 500 million clinical

cases, and 1-2 million deaths per year, (WHO, 2010). In Africa it accounts for 90% of cases

of malaria occurring worldwide. One African child dies of malaria every 30 seconds,

responsible for 1 in 4 childhood death and accounts for 10% of Africa‟s diseases burden,

(Agomo et., 2007; WHO, 2010). Nigeria accounts for 25% of malaria cases in WHO

African region. It is responsible for 50% of all clinic attendance affecting mainly children

under the age of 5 years and pregnant women (WHO, 2010). In children an estimated 56

million episodes is under 5 years per year, and is the major causes of poor child