Biotechnol. Appl. Biochem. (2007) 46, 69–72 (Printed in Great Britain) doi:10.1042/BA20060105 69 Erythropoietic and anti-obesity effects of Garcinia cambogia (bitter kola) in Wistar rats Kayode Alaba Oluyemi* 1 , Idowu O. Omotuyi†, Olusegun R. Jimoh‡, Olamide A. Adesanya*, Chia L. Saalu* and Sunday J. Josiah† *Department of Anatomy, Igbinedion University, Okada, P.M.B. 0006, Benin City, Edo State, Nigeria, †Department of Biochemistry, Igbinedion University, Okada, P.M.B. 0006, Benin City, Edo State, Nigeria, and ‡Department of Anatomy, University of Ilorin, P.M.B. 1515, Kwara state, Nigeria The anti-obesity and erythropoietic effects of crude ethanolic extracts of Garcinia cambogia (bitter kola) seeds on Wistar rats (Rattus norvegicus) were investi- gated. The rats were divided into three dosage groups: A (0 mg/kg of body weight), B (200 mg/kg) and C (400 mg/kg). Weight changes, plasma lipoprotein levels and the lipid profile of the liver, gastrointestinal system and adipose tissue were monitored as indices for anti- obesity, while the RBC (red blood cell) count (assessed by using a haemocytometer) was monitored as a measure of erythropoiesis. The extract was admin- istered by gavage for 5 weeks. The results for each test group was compared statistically with those for the control (P < 0.05). Analysis of the results showed a sig- nificant increase in RBC counts in both test groups and a decrease in weights of experimental animals. There was a dose-dependent decrease in the plasma level of very-low-density lipoprotein and a dose-dependent increase in the level of chylomicrons. There was a slight, but significant, decrease in the level of high-density lipoprotein and a significant increase in the level of LDL (low-density lipoprotein). There was significant dose- dependent decrease in the TAG (triacylglycerol) pool of adipose tissue and the liver of the test groups, but a significant increase in the TAG pool of the gastro- intestinal system. The increase in the TAG pool of the gastrointestinal system is possibly compensatory. The results therefore confirm that ethanolic extracts of G. cambogia seeds have both haematologically enhanc- ing and anti-obesity effects. The decrease in the high- density-lipoprotein level and an increase in the LDL level may play an important role in cardiovascular disease. Introduction Historically, plants have served as a source of raw materials for drug development [1]. Several plants are now being used in part or as a whole to treat many diseases. Active components of these plants are now being investigated, extracted and developed into drugs with little or no negative effects or contraindication. One such plant is Garcinia cambogia (bitter kola or Malabar tamarind). G. cambogia has been used historically to treat respiratory infections such as sore throat and cough among the Yoruba race of West Africa. Early studies on G. cambogia seeds have confirmed that it has antifungal [2], anticancer [3,4], antihistamine [5], anti-ulcerogenic [6], antimicrobial [7] and antiviral effects [8]. The analysis of the whole G. cambogia pod showed that it contains 96 % seed and 4 % rind. The phytochemical constituents of G. cambogia include a dimeric flavonoid– biflavonoid, xanthone and benzophenones [2] accounting for the antioxidant properties of G. cambogia. (−)-Hydroxycitric acid is the principal acid of the fruit and the rind. This acid was shown to be a potent inhibitor of ATP-dependent citrate lyase, which catalyses the cleavage of citrate to oxaloacetate and acetyl-CoA [6]. This enzyme ensures the supply of acetyl-CoA, which is used by acetyl- CoA carboxylase, the regulatory enzyme of lipogenesis in the liver. This is also important in the regulation of bio- synthesis of endogenous lipids [9], the plasma level of the lipoproteins {VLDL (very-low-density lipoprotein), LDL (low-density lipoprotein) and HDL (high-density lipoprotein) [10]} and the distribution of the lipid in extrahepatic tissues, especially adipocytes, the storage site of body fats. The variation in the fat deposit in the adipose tissue affects the hypothalamic release of neuropeptidase Y, orexin A and orexin B, melanin-concentrating hormone and ghrelin production, which also affects the intake [11], digestion and intestinal absorption of food molecules. The plasma levels of chylomicrons as carriers of exogenous lipid is regulated by this mechanism [12]. G. cambogia is also reported to increase the level of peripheral testosterone [13]. This hormone plays a major role in the production of secondary sexual characteristics in males by altering the rate of expression of genes, particularly those related to the regulation of Key words: anti-obesity effect, erythropoiesis, Garcinia cambogia (bitter kola), lipoprotein, red blood cell. Abbreviations used: HDL, high-density lipoprotein; LDL, low-density lipoprotein; PL, plasma lipoprotein; RBC, red blood cell; TAG, triacylglycerol; VLDL, very-low-density lipoprotein. 1 To whom correspondence should be addressed (email kayodedanatomist@yahoo.com). C  2007 Portland Press Ltd