Results for non-significant effect of drinks on HDL are
in agreement with previous work of Gomikawa et al.
[22]. The effects could be due to presence of various
bioactive components present in green tea [4]. Roghani
and Baluchnejadmojarad [23] noted LDL reduction in
diabetic rat modeling with EGCG. The proposed mechanism
of LDL reduction by green tea catechins is through inhibition
of cholesterol synthesis and dietary cholesterol
Trial-I
Normal diet
120
140
160
180
200
220
240
260
280 Trial-II
High cholesterol diet
Trial-IV
Day-0W-1 W-2 W-3 W-4 W-5 W-6 W-7 W-8
High cholesterol + high sucrose diet
Trial-III
Weeks
Day-0W-1 W-2 W-3 W-4 W-5 W-6 W-7 W-8
High sucrose diet
120
140
160
180
200
220
240
260
280
T1 = Control T2 = Drink containing catechins T3 = Drink containing EGCG
Figure 3 Body weight in different studies (g/rat) to show the effects of functional drinks in different studies fed with diets i.e. normal,
high sucrose, high cholesterol, and high sucrose + high cholesterol. The results showed significant variations in different trial. However, the
effects are directly linked with feed intake as higher feed intake results in higher body weight and vice versa.
Ahmad et al. Journal of Translational Medicine (2015) 13:79 Page 6 of 9
Table 2 Effect of functional drinks on lipid profile in rats
Studies Treatments
T1 T2 T3
Cholesterol (mg/dL) Trial-I 78.64 ± 3.07a 74.73 ± 2.34b 76.46 ± 2.42ab
Trial-II 147.02 ± 7.83a 126.42 ± 4.47b 130.09 ± 7.77b
Trial-III 128.74 ± 5.60a 113.84 ± 6.93b 116.79 ± 5.36b
Trial-IV 155.02 ± 8.36a 132.67 ± 6.90b 135.42 ± 6.33b
HDL (mg/dL) Trial-I 34.64 ± 2.57 35.80 ± 1.79 35.47 ± 2.25
Trial-II 56.29 ± 3.71 58.30 ± 4.47 57.80 ± 4.15
Trial-III 46.95 ± 2.59 48.27 ± 3.53 47.80 ± 3.43
Trial-IV 58.86 ± 3.01 60.35 ± 4.66 59.27 ± 2.61
LDL (mg/dL) Trial-I 30.34 ± 1.43a 25.55 ± 1.22b 27.41 ± 1.46ab
Trial-II 69.68 ± 3.45a 48.47 ± 2.41b 52.17 ± 3.79b
Trial-III 64.66 ± 3.22a 50.36 ± 2.83b 52.42 ± 4.32b
Trial-IV 74.59 ± 4.95a 53.10 ± 3.45b 57.27 ± 4.98b
Triglycerides (mg/dL) Trial-I 68.30 ± 3.74 66.92 ± 3.61 67.89 ± 3.13
Trial-II 105.26 ± 6.02 98.23 ± 5.16 100.61 ± 7.71
Trial-III 85.63 ± 6.52a 76.06 ± 5.09b 82.86 ± 4.82ab
Trial-IV 107.85 ± 7.21a 94.38 ± 6.05b 96.10 ± 4.69b
Values are expressed as means ± SD.
Means carrying same letter in a row do not differ significantly.
Means showing different lettering in a row differed significantly at P < 0.05.
Trial-I: Normal diet.
Trial-II: High cholesterol diet.
Trial-III: High sucrose diet.
Trial-IV: High cholesterol + high sucrose diet.
T1: Control drink (without active ingredients).
T2: Drink containing catechins.
T3: Drink containing EGCG.
Table 3 Effect of functional drinks on glucose and insulin levels of rats
Studies Treatments
T1 T2 T3
Glucose (mg/dL) Trial-I 93.55 ± 6.01 92.44 ± 4.43 90.44 ± 4.79
Trial-II 105.60 ± 6.61 103.32 ± 5.26 101.51 ± 4.58
Trial-III 125.93 ± 5.47a 113.21 ± 7.25b 110.40 ± 5.85b
Trial-IV 130.05 ± 8.75a 121.07 ± 7.32b 119.57 ± 6.60b
Insulin (μU/mL) Trial-I 9.33 ± 0.51 9.15 ± 0.68 9.14 ± 0.71
Trial-II 11.05 ± 0.09 10.59 ± 0.15 10.34 ± 0.65
Trial-III 14.34 ± 0.41a 12.65 ± 0.57b 12.20 ± 0.49b
Trial-IV 16.34 ± 0.59a 14.20 ± 0.74b 13.65 ± 0.67b
Values are expressed as means ± SD.
Means carrying same letter in a row do not differ significantly.
Means showing different lettering in a row differed significantly at P < 0.05.
Trial-I: Normal diet.
Trial-II: High cholesterol diet.
Trial-III: High sucrose diet.
Trial-IV: High cholesterol + high sucrose diet.
T1: Control drink (without active ingredients).
T2: Drink containing catechins.
T3: Drink containing EGCG.
Ahmad et al. Journal of Translational Medicine (2015) 13:79 Page 7 of 9
absorption [24]. Crude catechins decrease plasma cholesterol
concentrations by upregulating LDL receptor. The
increase in the LDL receptor improves the uptake of low
density lipoprotein cholesterol from the blood circulation
[25]. Moreover, reduced expression of 3-hydroxy-3-methylglutaryl
coenzyme A reductase (HMGR) might be another
reason for hypocholesterolemic activity of green tea
as green tea EGCG also inhibits HMGR activity [26,27].
Low concentration of triglycerides by green tea might
result from suppressed expression of stearoyl-CoA desaturase
(SCD 1) gene. Because in liver triglyceride synthesis
depends on the expression of the SCD 1 gene, that is
involved in biosynthesis of oleate and palmitoleate, the
major monounsaturated fatty acids of triglycerides. However,
Watanabe et al. [28] is of the view that reduced activity
of acetyl-Co A by green tea catechins is a reason for
low triglycerides synthesis.
Reduced glucose level by green tea is supported by the
work of Polychronopoulos et al. [29] that stated that there
occurs inverse relation between green tea and blood
glucose. The antihyperglycemic effect of green tea may
be due to activated uptake of glucose, inhibited intestinal
glucose transporter and decreased expression of
gluconeogenesis controlling genes [30]. EGCG exhibits
hypoglycemic potential b