CHAPTER ONE
INTRODUCTION
1.1 INTRODUCTION
Compelling evidence suggests that exposure to an adverse fetal environment may enhance susceptibility to a number of chronic diseases in the future life of the offspring(Buzinaro et al, 2008; Simeoni and Barker, 2009).
Diabetes mellitus is a condition that occur during pregnancy that can substantially influence the development of the offspring in utero and postnatally. Diabetes mellitus is now a pandemic, affecting about 10million Nigerians (Ogbera et al, 2005) and about 350 million people worldwide (Ezzati et al, 2011) among who are pregnant women. It is well documented that the combined stress of diabetes mellitus and pregnancy creates a metabolic environment that is often life threatening to both the mother and the fetus (Freinkel, 1980; Metzger, 1991).
Hence, pregnancy among women that have pre-existing diabetes or gestational diabetes is associated with increased rate of adverse outcome for both mother and fetus (Kingsley, 2007; Shefali et al., 2006).
This is primarily due to altered maternal intrauterine environment, creating a situation in which the fetus is exposed to abnormal metabolic substrate (glucose) levels (Van Assche et al, 1991). There is an increased placental transfer of glucose from mother to fetus because of increased availability at the maternal site (Thomas et al, 1990). The compromised metabolic state of the fetus subsequently precipitates a variety of complications associated with ‘‘fuel-mediated teratogenesis’’ (e.g., hyperglycemia, hyperinsulinemia and macrosomia) (Freinkel, 1980; Metzger, 1991). One particularly devastating effect of diabetic pregnancy is that these conditions affect the fetus not only in utero, but also extend throughout the life of the offspring (Padilha et al, 2007; George et al, 2010). Additionally, maternal hyperglycemia stimulates abnormal fetal growth (Aberg et al, 2001) due to the greater availability of glucose in the blood flow (Maayan-Metzger et al, 2009), and this high weight fetus carries a high risk for 17 developing insulin resistance, glucose intolerance, obesity, and type 2 diabetes mellitus in childhood, adolescence and adulthood (Buzinaroet al, 2008; Simeoni and Barker, 2009)
The chances of reducing this poor outcome of pregnancy among diabetics are intricately related with the level of glycemic control (Shefali et al., 2006).
The fact that the economic cost of managing diabetes mellitus is high confers a very important role to medicinal plants in the management of diabetes mellitus especially in developing countries where resources are meager.
Consequently, a number of plants indigenous to Nigeria have been studied, and found to have hypoglycemic effects. These effects were traced to phytochemicals like alkanoids called active principles that can be extracted from plants(Ojewale, 2006; Osadebe et al., 2004). One of such anti-diabetic plants is Garcinia kola, commonly known as Bitter kola. It is an evergreen tree, indigenous to sub-Saharan Africa and belongs to a family of tropical plants called Guttifera (Ofusori et al., 2008). The seed is a masticatory, used for traditional hospitality in cultural and social ceremonies. Every part of the plant has shown to be of medicinal importance and has a wide range of medicinal effects, hence the name ‘wonder plant’ as it is commonly called.
Among the litany of its medicinal effects are; antidiabetic effects (Iwu et al, 1990), weight reducing effets (Koshy et al., 2001), leptin like action (Hayamizu et al., 2003), antihepatotoxic effects (Akintonwa and Essien, 1990), antioxidative stress and anti DNA 18 damage (Farombi, et al., 2004), detoxification of the toxic effects of other chemicals (Esimoneet al., 2002; Nwokocha et al, 2011), etc.
1.2 JUSTIFICATION FOR THE STUDY
Diabetes mellitus is fast becoming the most common type of disease in school children (Pontiroli, 2004). This may be as a result of the reported more than doubling in therate of diabetes among expectant mothers between 2002 and 2008 (Lawrence et al., 2008).
The economic cost of managing diabetes is high. As a result, in the developing countries where resources are meager, there is a shift from contemporary to orthodox medicine since medicinal plants are relatively easier to find and less expensive alternative.
Coincidentally, some of the commonly consumed plant materials in Nigeria have been found to poses anti-diabetic properties. One of such anti-diabetic plantmaterials Bitter kola seed is used as a stimulant. It is also taken by pregnant women to stop nausea.
Although Bitter kolaseed is a known anti-diabetic, there is paucity of data on;
(1) Its effects on pregnancies complicated by diabetes mellitus
(2) Early postnatal development of the offspring’s of such pregnancies.
Hence, the present study was therefore designed to investigate these.
1.3 AIM
The aim of this study is to determine the effect of consumption of Garcinia kola extract by diabetic pregnant rats on the pregnancy outcome and early postnatal development of their offspring.
1.4 OBJECTIVES
To determine the effect of consumption of Bitter kolaextract by diabetic pregnant rats on;
i. The litter size.
ii. The early postnatal growth of the offsprings (from birth to weaning).
iii. The glucose profile of the offsprings at weanin
1.5 OPERATIONAL DEFINITION OF TERMS
Alloxan diabetes: A type of diabetes induced in rodens by the injection of alloxan hydrate. 20 Pregnancy weight gain:The weight gain during pregnancy.
Programming: The process whereby a stimulus or stress at a critical period of development of the rats results in a lasting or lifelong effect.
Teratogenic: Capable of causing developmental abnormalities in the fetus
Diabetic pregnancy:Pregnancy complicated by diabetes mellitus irrespective of the type.
Early Postnatal development: This is the developmental processes that occur in the offsprings from the time of birth to the weaning day.
Gestation period: The period (in days) between the time when spermatozoa were first seen in vaginal smear and the time of delivery.
Glucose drain: The transfer of glucose from the maternal to fetal blood.
In-utero: Events occurring inside the uterus.
Litter Size: The number of offspring delivered by a pregnant rat.
Litter weight: The weight of the offsprings at birth (g).
Perinatal: Events that occur around the time of birth.
Pregestational (Pre-existing) diabetes: Diabetes existing before pregnancy, irrespective of the type.
Pregnancy weight gain: The weight gain during pregnancy.
Programming: The process whereby a stimulus or stress at a critical period of development of the rats results in a lasting or lifelong effect.
Teratogenic: Capable of causing developmental abnormalities in the fetus..
EFFECTS OF AQUEOUS EXTRACT OF BITTER KOLA (GARCINIA KOLA) ON THE PREGNANCY OUTCOME AND EARLY POSTNATAL DEVELOPMENT OF THE OFFSPRINGS OF DIABETIC PREGNANT RATS
