EFFECT OF Garcinia cambogia EXTRACT ON SERUM LEPTIN, GHRELIN, ADIPONECTIN AND INSULIN LEVELS AND BODY WEIGHTS IN RATS FED WITH HIGH LIPID DIET

Abstract

Garcinia cambogia (malabar tamarind, bitter kola) is seen abundantly in the evergreen forests of Konkan in South India. Hydroxycitric acid, mainly obtained from Garcinia cambogia, was identified by the end of the 1960’s as a strong competitive inhibitor of the extramitochondrial enzyme adenosine triphosphate citrate lyase. The objective of this study was to present the effect of Garcinia cambogia extract known as weakener on the supportive or preventive hormones (leptin, ghrelin, adiponectin, insulin) of obesity in the rats fed the diet containing hydrogenated-vegetable oil and cholesterol. For this purpose, thirty female 5-6 months-old Sprague-Dawley rats were randomly assigned to three groups. Each group consisted of 10 rats. Group 1 (as control group) was fed with a basal diet while the diets of Groups 2 and 3 contained the hydrogenated-vegetable oil (20%) and cholesterol (1%) beside of other nutrients. Garcinia cambogia extract containing 6% hydroxycitric acid was added to the diet w/w of Group 3 after Day 30 up until Day 60. Blood samples were taken from animals on Days 0, 30 and 60 of the trial period. Body weights were weighed in the blood sampling days before sampling. Serum leptin, ghrelin, adiponectin, insulin levels and body weights were not significantly different between groups in the each sampling day. Serum leptin levels were significantly higher on Day 60 than on Days 0 and 30 in Groups 2 and 3. Serum ghrelin levels in Group 3 significantly decreased on Day 30 and significantly increased on Day 60. Serum adiponectin levels in Group 1 were significantly lower on Day 0 than on other days. The levels in Group 3 were significantly higher on Day 60 than on Day 0. The serum insulin levels and body weights were not significantly different between the days in each group. In conclusion, the high lipid diet in doses used in the study (20% hydrogenated-vegetable oil and 1% cholesterol) did not create fat accumulation or obesity in Sprague Dawley rats. Addition of Garcinia cambogia to diet (6%, w/w) of rats fed with the high lipid diet indicated no effect on weight gain. The evidences obtained from this research do not support the role of Garcinia cambogia plant spreadly used as a weight loss facilitator. Key words: adiponectin; Garcinia cambogia; ghrelin; insulin; leptin VPLIV IZVLEČKA RASTLINE Garcinia cambogia NA RAVEN LEPTINA, GRELINA, ADIPONEKTINA IN INZULINA TER NA TELESNO TEŽO PRI PODGANAH, HRANJENIH S HRANO Z VISOKO VSEBNOSTJO MAŠČOB Garcinia cambogia je pogosta rastlina v tropskih gozdovih južne Indije. Hidroksicitronska kislina, ki je v velikih kolièinah v rastlini Garcinia cambogia, je bila v šestdesetih letih prejšnjega stoletja prepoznana kot močan kompetitivni zaviralec zunajmitohondrijskega encima ATP-citratna liaza. Namen raziskave je bil ugotoviti, ali izvleček rastline Garcinia cambogia lahko vpliva na izločanje hormonov, ki sodelujejo pri urejanjeu telesne teže (leptin, grelin, adiponektin, inzulin) pri podganah, hranjenih s hrano z visoko vsebnostjo maščob (rastlinska olja in holesterol). V raziskavo je bilo vkljuèenih 30 podganjih samic seva SpragueDawley, starih 5 do 6 mesecev, ki so bile nakljuèno razporejene v eno od treh poskusnih skupin. Podgane iz prve skupine so prejemale navadno hrano, podgane iz druge skupine pa hrano z dodanimi 20 % rastlinskih olj ter 1 % holesterola. Izvleček Garcinie cambogie je bil dodajan v hrano podganam iz tretje skupine, tako da so prejemale v hrani 6 % hidroksicitronske kisline. Podgane so bile v poskusu 60 dni, s tem da so živali iz tretje skupine prejemale v hrani izvleèek Garcinie cambogie od 30. do 60. dneva poskusa. Podganam smo odvzeli kri 1., 30. in 60. dan poskusa, ko so bile tudi stehtane. Raven letpina je bila v skupinah 2 in 3 statistièno značilno višja na 60. dan v primerjavi s 1. in 30. dnevom. Raven grelina je bila v skipini 3 30. dan poskusa statistièno znaèilno nižja, 60. dan pa statistično značilno višja. Raven adiponektina je bila v skupini 1 statistièno znaèilno višja 30. in 60. dan poskusa. Raven inzulina ter telesna teèa pa se nista razlikovali med skupinami v nobeni časovni toèki. Ugotovimo lahko, da hrana z visoko vsebnostjo maščob ni povzročila v časovnem okviru raziskave debelosti, prav tako pa izvleček rastline Garicnia cambogia ni vplival na telesno teèo ali na raven hormonov in torej ni primeren kandidat za naravno zdravilo za pomoč pri hujšanju. Ključne besede: adiponectin; Garcinia cambogia; ghrelin; insulin; leptin