The effect of chlorogenic acid
enriched coffee on glucose absorption in healthy volunteers and its effect on
body mass when used long-term in overweight and obese people.
The results from a clinical study
performed in 12 healthy volunteers with different coffee products containing
glucose show that instant coffee enriched with chlorogenic acid induced a
reduction in the absorption of glucose of 6.9% compared with the control. No
such effects were seen with normal or decaffeinated instant coffee. In a
second, comparative, randomized, double-blind, 12-week study we investigated
the effect on the body mass of 30 overweight people, compared with normal
instant coffee. The average losses in mass in the chlorogenic acid enriched
and normal instant coffee groups were 5.4 and 1.7 kg, respectively. We
conclude that chlorogenic acid enriched instant coffee appears to have a
significant effect on the absorption and utilization of glucose from the diet.
This effect, if the coffee is used for an extended time, may result in
reduced body mass and body fat when compared with the use of normal instant
coffee.
J Int Med Res. 2007 Nov-Dec;35(6):900-8
Acute effects of decaffeinated
coffee and the major coffee components chlorogenic acid and trigonelline on
glucose tolerance.
OBJECTIVE: Coffee consumption has
been associated with lower risk of type 2 diabetes. We evaluated the acute
effects of decaffeinated coffee and the major coffee components chlorogenic
acid and trigonelline on glucose tolerance. RESEARCH DESIGN AND METHODS: We
conducted a randomized crossover trial of the effects of 12 g decaffeinated
coffee, 1 g chlorogenic acid, 500 mg trigonelline, and placebo (1 g mannitol)
on glucose and insulin concentrations during a 2-h oral glucose tolerance
test (OGTT) in 15 overweight men. RESULTS: Chlorogenic acid and trigonelline
ingestion significantly reduced glucose (-0.7 mmol/l, P = 0.007, and -0.5
mmol/l, P = 0.024, respectively) and insulin (-73 pmol/l, P = 0.038, and -117
pmol/l, P = 0.007) concentrations 15 min following an OGTT compared with
placebo. None of the treatments affected insulin or glucose area under the
curve values during the OGTT compared with placebo. CONCLUSIONS: Chlorogenic
acid and trigonelline reduced early glucose and insulin responses during an
OGTT.
Diabetes Care. 2009 Jun;32(6):1023-5
Inhibitory effect of green coffee
bean extract on fat accumulation and body weight gain in mice.
BACKGROUND: An epidemiological
study conducted in Italy indicated that coffee has the greatest antioxidant
capacity among the commonly consumed beverages. Green coffee bean is rich in
chlorogenic acid and its related compounds. The effect of green coffee bean
extract (GCBE) on fat accumulation and body weight in mice was assessed with
the objective of investigating the effect of GCBE on mild obesity. METHODS:
Male ddy mice were fed a standard diet containing GCBE and its principal
constituents, namely, caffeine and chlorogenic acid, for 14 days. Further, hepatic
triglyceride (TG) level was also investigated after consecutive
administration (13 days) of GCBE and its constituents. To examine the effect
of GCBE and its constituents on fat absorption, serum TG changes were
evaluated in olive oil-loaded mice. In addition, to investigate the effect on
hepatic TG metabolism, carnitine palmitoyltransferase (CPT) activity in mice
was evaluated after consecutive ingestion (6 days) of GCBE and its
constituents (caffeine, chlorogenic acid, neochlorogenic acid and feruloylquinic
acid mixture). RESULTS: It was found that 0.5% and 1% GCBE reduced visceral
fat content and body weight. Caffeine and chlorogenic acid showed a tendency
to reduce visceral fat and body weight. Oral administration of GCBE (100 and
200 mg/kg. day) for 13 days showed a tendency to reduce hepatic TG in mice.
In the same model, chlorogenic acid (60 mg/kg. day) reduced hepatic TG level.
In mice loaded with olive oil (5 mL/kg), GCBE (200 and 400 mg/kg) and
caffeine (20 and 40 mg/kg) reduced serum TG level. GCBE (1%), neochlorogenic
acid (0.028% and 0.055%) and feruloylquinic acid mixture (0.081%)
significantly enhanced hepatic CPT activity in mice. However, neither
caffeine nor chlorogenic acid alone was found to enhance CPT activity.
CONCLUSION: These results suggest that GCBE is possibly effective against
weight gain and fat accumulation by inhibition of fat absorption and
activation of fat metabolism in the liver. Caffeine was found to be a
suppressor of fat absorption, while chlorogenic acid was found to be
partially involved in the suppressive effect of GCBE that resulted in the
reduction of hepatic TG level. Phenolic compounds such as neochlorogenic acid
and feruloylquinic acid mixture, except chlorogenic acid, can enhance hepatic
CPT activity.
BMC Complement Altern Med. 2006 Mar 17;6:9
Coffee polyphenols suppress
diet-induced body fat accumulation by downregulating SREBP-1c and related
molecules in C57BL/6J mice.
The prevalence of obesity is
increasing globally, and obesity is a major risk factor for type 2 diabetes
and cardiovascular disease. We investigated the effects of coffee polyphenols
(CPP), which are abundant in coffee and consumed worldwide, on diet-induced
body fat accumulation. C57BL/6J mice were fed either a control diet, a
high-fat diet, or a high-fat diet supplemented with 0.5 to 1.0% CPP for 2-15
wk. Supplementation with CPP significantly reduced body weight gain,
abdominal and liver fat accumulation, and infiltration of macrophages into
adipose tissues. Energy expenditure evaluated by indirect calorimetry was
significantly increased in CPP-fed mice. The mRNA levels of sterol regulatory
element-binding protein (SREBP)-1c, acetyl-CoA carboxylase-1 and -2,
stearoyl-CoA desaturase-1, and pyruvate dehydrogenase kinase-4 in the liver
were significantly lower in CPP-fed mice than in high-fat control mice.
Similarly, CPP suppressed the expression of these molecules in Hepa 1-6
cells, concomitant with an increase in microRNA-122. Structure-activity
relationship studies of nine quinic acid derivatives isolated from CPP in
Hepa 1-6 cells suggested that mono- or di-caffeoyl quinic acids (CQA) are
active substances in the beneficial effects of CPP. Furthermore, CPP and
5-CQA decreased the nuclear active form of SREBP-1, acetyl-CoA carboxylase
activity, and cellular malonyl-CoA levels. These findings indicate that CPP
enhances energy metabolism and reduces lipogenesis by downregulating SREBP-1c
and related molecules, which leads to the suppression of body fat
accumulation.
Am J Physiol Endocrinol Metab. 2011 Jan;300(1):E122-33
National, regional, and global
trends in fasting plasma glucose and diabetes prevalence since 1980:
systematic analysis of health examination surveys and epidemiological studies
with 370 country-years and 2•7 million participants.
BACKGROUND: Data for trends in
glycaemia and diabetes prevalence are needed to understand the effects of
diet and lifestyle within populations, assess the performance of
interventions, and plan health services. No consistent and comparable global
analysis of trends has been done. We estimated trends and their uncertainties
in mean fasting plasma glucose (FPG) and diabetes prevalence for adults aged
25 years and older in 199 countries and territories. METHODS: We obtained
data from health examination surveys and epidemiological studies (370
country-years and 2•7 million participants). We converted systematically
between different glycaemic metrics. For each sex, we used a Bayesian
hierarchical model to estimate mean FPG and its uncertainty by age, country, and
year, accounting for whether a study was nationally, subnationally, or
community representative. FINDINGS: In 2008, global age-standardised mean FPG
was 5•50 mmol/L (95% uncertainty interval 5•37-5•63) for men and 5•42 mmol/L
(5•29-5•54) for women, having risen by 0•07 mmol/L and 0•09 mmol/L per
decade, respectively. Age-standardised adult diabetes prevalence was 9•8%
(8•6-11•2) in men and 9•2% (8•0-10•5) in women in 2008, up from 8•3%
(6•5-10•4) and 7•5% (5•8-9•6) in 1980. The number of people with diabetes
increased from 153 (127-182) million in 1980, to 347 (314-382) million in
2008. We recorded almost no change in mean FPG in east and southeast Asia and
central and eastern Europe. Oceania had the largest rise, and the highest
mean FPG (6•09 mmol/L, 5•73-6•49 for men; 6•08 mmol/L, 5•72-6•46 for women)
and diabetes prevalence (15•5%, 11•6-20•1 for men; and 15•9%, 12•1-20•5 for
women) in 2008. Mean FPG and diabetes prevalence in 2008 were also high in
south Asia, Latin America and the Caribbean, and central Asia, north Africa,
and the Middle East. Mean FPG in 2008 was lowest in sub-Saharan Africa, east
and southeast Asia, and high-income Asia-Pacific. In high-income subregions,
western Europe had the smallest rise, 0•07 mmol/L per decade for men and 0•03
mmol/L per decade for women; North America had the largest rise, 0•18 mmol/L
per decade for men and 0•14 mmol/L per decade for women. INTERPRETATION:
Glycaemia and diabetes are rising globally, driven both by population growth
and ageing and by increasing age-specific prevalences. Effective preventive
interventions are needed, and health systems should prepare to detect and
manage diabetes and its sequelae.
Lancet. 2011 Jul 2;378(9785):31-40
A large proportion of prediabetes
and diabetes goes undiagnosed when only fasting plasma glucose and/or HbA1c
are measured in overweight or obese patients.
AIMS: The purposes of the study
were to determine the prevalence of unrecognized dysglycaemia in overweight
(body mass index [BMI] 25-29.9 kg/m(2)) and obese (BMI ≥30 kg/m(2)) patients,
to assess the extent to which measures of fasting plasma glucose (FPG) and/or
HbA(1c), compared with oral glucose tolerance tests (OGTTs), misdiagnose
dysglycaemia, and to determine the factors associated with an isolated
abnormal post-OGTT glucose value. METHODS: OGTT was performed and HbA(1c) was
measured in 1283 inpatients with BMI scores ≥ 25 kg/m(2) and no history of
dysglycaemia. RESULTS: Prediabetes was found in 257 (20.0%) subjects (197
with impaired glucose tolerance, 29 with impaired fasting glucose, 31 with
both) and diabetes in 77 (6.0%), including 22 with FPG ≥ 7 mmol/L (WHO
definition). The sensitivity of FPG >6 mmol/L, FPG >5.5 mmol/L, HbA(1c)
≥ 6% and the recommendations of the French National Agency of Accreditation
and Evaluation in Health Care (ANAES) to identify patients with abnormal
OGTTs was 29.9, 41.3, 36.8 and 15.6%, respectively. The factors that were
independently associated with diabetes in obese women with FPG <7 mmol/L
were age (per 10 years: OR 1.54 [1.00-2.11]; P=0.049) and FPG (OR 6.1
[1.4-30.0]; P=0.014), whereas age (OR 1.26 [1.09-1.44]; P<0.01) and waist
circumference (per 10 cm: OR 1.17 [1.01-1.33]; P<0.05) were independently
associated with dysglycaemia in obese women with FPG <6.1 mmol/L. CONCLUSION:
In overweight and obese patients: dysglycaemia is commonly seen; FPG alone,
compared with OGTT, failed to diagnose 70% of dysglycaemia cases; FPG >5.5
mmol/L and HbA(1c) ≥ 6.0% are not necessarily substitutes for OGTT; and older
age and larger waist circumference should be used to select those obese women
with normal FPG who might further benefit from OGTTs to diagnose
dysglycaemia.
Diabetes Metab. 2010 Sep;36(4):312-8
Chlorogenic acid reduces the
plasma glucose peak in the oral glucose tolerance test: effects on hepatic
glucose release and glycaemia.
The effects of chlorogenic acid
(CA) on hepatic glucose output, blood glucose levels and on glucose tolerance
were analysed. Hepatic uptake of CA and its effects on hepatic catabolism of
L-alanine and glucose-6-phosphatase (G-6-Pase) activity were also evaluated.
CA (1 mM) inhibited about 40% of G-6-Pase activity (p < 0.05) in the
microsomal fraction of hepatocytes, but no effect was observed on production
of glucose from gluconeogenesis or on L-alanine catabolism, at various
concentrations of CA (0.33, 0.5 and 1 mM), in liver perfusion experiments.
Since there were indications of a lack of uptake of CA by the liver, it is
possible that this compound did not reach sufficiently high intracellular
levels to inhibit the target enzyme. Accordingly, intravenous administration
of CA also failed to provoke a reduction in blood glucose levels. However, CA
did promote a significant reduction (p < 0.05) in the plasma glucose peak
at 10 and 15 min during the oral glucose tolerance test, probably by
attenuating intestinal glucose absorption, suggesting a possible role for it
as a glycaemic index lowering agent and highlighting it as a compound of
interest for reducing the risk of developing type 2 diabetes.
Cell Biochem Funct. 2008 Apr;26(3):320-8
Characterization of inhibitors of
postprandial hyperglycemia from the leaves of Nerium indicum.
Nerium indicum is an
India-Pakistan-originated shrub belonging to the oleander family. The
ingestion of leaves of N. indicum before a meal is known to effect the
lowering of postprandial glucose levels in type II diabetic patients and this
plant is now used as a folk remedy for type II diabetes in some regions of
Pakistan. In the present study, the hot-water extract of N. indicum leaves
was found to reduce the postprandial rise in the blood glucose when maltose
or sucrose was loaded in rats. It was also found that the extract strongly
inhibited alpha-glucosidase, suggesting that the suppression of the
postprandial rise in the blood glucose is due to the occurrence of some
inhibitors of alpha-glucosidase in the leaves. We, therefore, tried to
isolate the active principles from the leaf extract, using
alpha-glucosidase-inhibitory activity as the index. Employing Sephadex G-15,
silica gel and reversed-phase HPLC, we isolated two active compounds. The UV,
mass and NMR spectrometric analyses established that the chemical structures
of these compounds are 3-O-caffeoylquinic acid (chlorogenic acid) and its
structural isomer, 5-O-caffeoylquinic acid. Both compounds were shown to
inhibit alpha-glucosidases in a non-competitive manner. The authentic
chlorogenic acid was found to suppress the postprandial rise in the blood
glucose in rats and also inhibited the absorption of the glucose moiety from
maltose and glucose in the everted gut sac system prepared from rat
intestine. These results demonstrate that chlorogenic acid is one of the
major anti-hyperglycemic principles present in the leaves of N. indicum.
Furthermore, among polyphenol compounds tested, quercetin and catechins were
shown to have strong inhibitory activity against alpha-glucosidase.
J Nutr Sci Vitaminol (Tokyo).2007 Apr;53(2):166-73
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