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Effects of Aloe vera Supplementation in Subjects with Prediabetes/Metabolic Syndrome

Authors:
  • Unigen Pharmaceuticals

Abstract and Figures

Background: Metabolic syndrome affects 1 in 3 U.S. adults. The primary target of treatment of patients with metabolic syndrome is therapeutic lifestyle change. Numerous animal trials have reported positive effects of Aloe vera in in vivo models of diabetes, but there is a paucity of controlled clinical trials in patients with prediabetes. Thus, the objective of this pilot study was to examine the effect of aloe compared to placebo on fasting blood glucose, lipid profile, and oxidative stress in subjects with prediabetes/metabolic syndrome. Methods: This was a double-blind, placebo-controlled Institutional Review Board (IRB)-approved pilot study of two aloe products (UP780 and AC952) in patients with prediabetes over an 8-week period. A total of 45 subjects with impaired fasting glucose or impaired glucose tolerance and having two other features of metabolic syndrome were recruited (n=15/group). Parameters of glycemia [fasting glucose, insulin, homeostasis model assessment (HOMA), glycosylated hemoglobin (HbA1c), fructosamine, and oral glucose tolerance test (OGTT)] and oxidative stress (urinary F2-isoprostanes) were measured along with lipid profile and high-sensitivity C-reactive protein (hsCRP) levels before and after supplementation. Results: There were no significant baseline differences between groups. Compared to placebo, only the AC952 Aloe vera inner leaf gel powder resulted in significant reduction in total and low-density lipoprotein cholesterol (LDL-C) levels, glucose, and fructosamine. In the UP780 Aloe vera inner leaf gel powder standardized with 2% aloesin group, there were significant reductions in HbA1c, fructosamine, fasting glucose, insulin, and HOMA. Only the UP780 aloe group had a significant reduction in the F2-isoprostanes compared to placebo. Conclusions: Standardized aloe preparations offer an attractive adjunctive strategy to revert the impaired fasting glucose and impaired glucose tolerance observed in conditions of prediabetes/metabolic syndrome.
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ORIGINAL ARTICLE
Effects of Aloe vera Supplementation in Subjects
with Prediabetes/Metabolic Syndrome
Sridevi Devaraj, Ph.D., DABCC,
1
Mesfin Yimam, D.V.M., M.S.,
2
Lidia A. Brownell, M.S.,
2
Ishwarlal Jialal, M.D., Ph.D.,
3
Sital Singh, B.S.,
3
and Qi Jia, Ph.D.
2
Abstract
Background: Metabolic syndrome affects 1 in 3 U.S. adults. The primary target of treatment of patients with
metabolic syndrome is therapeutic lifestyle change. Numerous animal trials have reported positive effects of Aloe
vera in in vivo models of diabetes, but there is a paucity of controlled clinical trials in patients with prediabetes.
Thus, the objective of this pilot study was to examine the effect of aloe compared to placebo on fasting blood
glucose, lipid profile, and oxidative stress in subjects with prediabetes/metabolic syndrome.
Methods: This was a double-blind, placebo-controlled Institutional Review Board (IRB)–approved pilot study of
two aloe products (UP780 and AC952) in patients with prediabetes over an 8-week period. A total of 45 subjects
with impaired fasting glucose or impaired glucose tolerance and having two other features of metabolic syn-
drome were recruited (n=15/group). Parameters of glycemia [fasting glucose, insulin, homeostasis model as-
sessment (HOMA), glycosylated hemoglobin (HbA1c), fructosamine, and oral glucose tolerance test (OGTT)]
and oxidative stress (urinary F2-isoprostanes) were measured along with lipid profile and high-sensitivity C-
reactive protein (hsCRP) levels before and after supplementation.
Results: There were no significant baseline differences between groups. Compared to placebo, only the AC952
Aloe vera inner leaf gel powder resulted in significant reduction in total and low-density lipoprotein cholesterol
(LDL-C) levels, glucose, and fructosamine. In the UP780 Aloe vera inner leaf gel powder standardized with 2%
aloesin group, there were significant reductions in HbA1c, fructosamine, fasting glucose, insulin, and HOMA.
Only the UP780 aloe group had a significant reduction in the F2-isoprostanes compared to placebo.
Conclusions: Standardized aloe preparations offer an attractive adjunctive strategy to revert the impaired fasting
glucose and impaired glucose tolerance observed in conditions of prediabetes/metabolic syndrome.
Introduction
Metabolic syndrome, also referred to as prediabetes,
is a cluster of interrelated common clinical disorders,
including obesity, insulin resistance, glucose intolerance,
hypertension, and dyslipidemia [hypertriglyceridemia and
low high-density lipoprotein cholesterol (HDL-C) levels],
which are established criteria for diagnosing metabolic syn-
drome in 2001.
1–3
Five criteria were selected by The Adult
Treatment Panel III (ATP III) of the National Cholesterol
Education Program (NCEP) to identify individuals with
metabolic syndrome—abdominal obesity, impaired fasting
glucose, high triglyceride (TG) and low HDL-C concentra-
tions, and increased blood pressure.
1–3
Metabolic syndrome
is diagnosed when any three of the components are present
in an individual. The metabolic syndrome is highly prevalent
worldwide and is associated with a greater risk of athero-
sclerotic cardiovascular disease than any of its individual
components and leads to a five-fold increase in diabetes and
a two-fold increase in cardiovascular disease. One in 3 in-
dividuals in the United States has metabolic syndrome. The
primary target of treatment of patients with metabolic syn-
drome is therapeutic lifestyle changes, which are difficult to
achieve.
Numerous animal trials have reported positive effects of Aloe
vera in in vivo models of diabetes, including lower fasting blood
glucose levels in alloxan-induced diabetic mice
4
;enhanced
glucose tolerance in glucose-loaded rats compared to normals
5
;
decreased glucose levels in streptozotocin-induced diabetic
rats
6
; improved liver gluconeogenesis in streptozotocin-induced
1
Department of Pathology and Immunology, Baylor College of Medicine, and Texas Children’s Hospital, Houston, Texas.
2
Unigen Inc., Seattle, Washington.
3
Laboratory for Atherosclerosis and Metabolic Research, UC Davis Medical Center, Sacramento, California.
METABOLIC SYNDROME AND RELATED DISORDERS
Volume X, Number X, 2012
Mary Ann Liebert, Inc.
Pp. 1–6
DOI: 10.1089/met.2012.0066
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111
diabetic rats
7
; decreased oxidative damage in the brains of
streptozotocin-induced diabetic mice
8
; decreased lipid perox-
idation in diabetic rat kidney
9
and liver
10
; and, in streptozotocin-
induced diabetic rats, decreased fasting glucose, normalized
lipids and fatty acid compositions in liver and kidney with
reducedlivertransaminases,andimprovedplasmainsulin
levels.
11
In contrast to animal studies, very few human clinical
trials have been reported in the literature. The two studies
most frequently cited to support the use of aloe in human
diabetes
12,13
have methodological flaws, which unfortu-
nately brings the significance of the results into question
(nonrandomized and nonblinded, apparently the same
population enrolled in both trials, the same decreases in both
blood glucose and serum triglycerides in the active groups
reported for both trials). A third study, evaluating the effects
of bread prepared with aloe gel consumed twice daily for
3 months in subjects with heart disease reported an inci-
dental finding of decreased fasting and postprandial blood
glucose levels in the subjects who also had a diagnosis
of diabetes.
14
Additionally, anecdotal reports of beneficial
effects of aloe in clinical diabetes also exist.
Recently, Huseini et al. examined the effect of Aloe vera gel
in hyperlipidemic type 2 diabetic patients who were already
on antiglycemic medications and reported that aloe gel
(300 mg twice a day for 2 months compared to placebo)
significantly lowered fasting blood glucose, glycosylated
hemoglobin (HbA1c), total and low-density lipoprotein
cholesterol (LDL-C) levels with no other side effects.
15
However, there are no reports of Aloe vera supplementation
in patients with prediabetes/metabolic syndrome. Thus, the
overall objective of this pilot study is to examine the effect of
two aloe products compared to placebo on fasting blood
glucose, lipid profile, and biomarkers of oxidative stress in
an 8-week study.
Subjects and Methods
This was a double-blind, placebo-controlled study. The
test products used were supplied by Unigen Inc., and in-
vestigators and volunteers were blinded to treatment as-
signment. The study received Institutional Review Board
(IRB) approval, and all subjects provided informed consent.
The products used were: Aloe product 1, UP780, an Aloe vera
inner leaf gel powder standardized with 2% aloesin, 500-mg
capsules, 1 capsule twice a day (b.i.d.); aloe product 2,
QMatrix or AC952, an Aloe vera inner leaf gel powder,
500-mg capsules, 1 capsule b.i.d; placebo capsules, 1 capsule
b.i.d. All products were dispensed to the subjects by the
Investigational Drug Services.
Study subjects
All study subjects had three features of the metabolic
syndrome, of which at least one feature was abnormal fast-
ing glucose (100–126 mg/dL) or abnormal glucose tolerance
[2-h oral glucose tolerance test (OGTT) >140–199 mg/dL]
but no history or current clinical evidence of diabetes (type I
or II). The selection criteria were as follows. Inclusion criteria
were: Females and males >18 years of age to 70 years of age;
prediabetes, defined as fasting plasma glucose (FPG) 90–
125 mg/dL, or 2-h OGTT 149–199 mg/dL plus any two of the
following criteria—waist >35 inches for women and >40
inches for men, triglycerides (TG) >150 mg/dL, HDL-C
<40 mg/dL in men and <50 mg/dL in women, and systolic
(SBP) or diastolic blood pressure (DBP) >130/85 mmHg.
Exclusion criteria were: Prior diagnosis of diabetes, preg-
nancy/lactation, history of gestational diabetes, currently on
any diabetes medication for any indication, history of any
other chronic disease, and known allergy to Aloe vera or any
products containing Aloe vera.
Only subjects who were willing to maintain a normal diet
and exercise at least 100 min per week were included in the
study. The subjects also abstained from any other dietary
supplements or weight loss programs during the study. All
subjects were at least 95% compliant throughout the study as
monitored by pill counts. Fasting blood was obtained at
baseline and following 8 weeks of supplementation. All
subjects underwent a 75-g OGTT and fasting glucose levels
at 0, 1, and 2 h was obtained and area under the curve (AUC)
was computed.
Routine laboratory tests were performed in the Clinical
Pathology laboratory, which is Clinical Laboratory Im-
provement Amendments (CLIA)–certified and included
complete blood counts, lipid profile, glucose, HbA1c, liver
function tests, creatinine, and insulin. Fructosamine levels
were measured by an enzymatic assay from Diazyme.
Briefly, the Diazyme Glycated Serum Protein (GSP) uses
proteinase K to digest GSP into low-molecular-weight gly-
cated protein fragments (GPF), and uses Diazyme’s specific
fructosaminase, a microorganism-originated amadoriase
to catalyze the oxidative degradation of Amadori product
GPF to yield PF or amino acids, glucosone, and hydrogen
peroxide (H
2
O
2
). The H
2
O
2
released is measured by a col-
orimetric Trinder end-point reaction. The absorbance at
600 nm is proportional to the concentration of fructosamine
in the sample.
Urine was collected at baseline and following 8 weeks
supplementation (24-h urine) for assessment of urinary
microalbumin:creatinine ratio in the Clinical Pathology
laboratory and for assessment of urinary F2-isoprostanes.
Urinary F2-isoprostanes were measured in urine
using the Cayman enzyme immunoassay as described
previously.
16
Table 1. Baseline Subject Characteristics
Placebo UP780 AC952
Week 0 Week 0 Week 0
Age (years) 50.5 10.7 50.6 10.6 57.2 9.5
BMI (kg/sqm) 35 6.1 33.8 7.2 35.3 5.8
Waist (inches) 42.3 5.7 40.3 5.2 42.7 4.6
M/F ratio 6/9 3/11 6/9
Total cholesterol (mg/dL) 196 31 210 27 206 29
Triglycerides (mg/dL) 121.4 63.2 146 121 156 87
HDL-C (mg/dL) 42 17 49 17 40 10
LDL-C (mg/dL) 129.5 22.1 135 25 135 26
HbA1c (%) 5.8 0.58 6.0 0.66 6.0 0.5
Glucose (mg/dL) 105 13 111 15 111 11
AUC Glu-OGTT 274 51 317 83 327 51
Insulin (mIU/mL) 19.9 8.0 16 11 18.6 14
Data are provided as mean standard deviation (SD).
BMI, body mass index; M/F, male/female; HDL-C, high-density
lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol;
HbA1c, glycosylated hemoglobin; AUC, area under the curve; Glu-
OGTT, glucose tolerance.
2 DEVARAJ ET AL.
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Statistics
All data were analyzed using SAS. Kruskal–Wallis anal-
ysis of variance (ANOVA) was computed followed by Wil-
coxon tests to assess statistical significance.
Results
A total of 45 subjects with impaired fasting glucose or
impaired glucose tolerance and having two other features of
the metabolic syndrome were recruited. A total of 14 subjects
in placebo, 14 subjects in UP780, and 15 subjects in AC952
groups completed the study, and results are reported. No
side effects were reported. Table 1 gives the subject charac-
teristics of all subjects in the study. There were no significant
baseline differences between groups. There were no significant
changes in complete blood count, aspartate aminotransferase
(AST), alanine aminotransferase (ALT), creatinine, before and
after supplementation (data not shown). Compliance was very
high (95%).
Table 2 provides the effect of Aloe vera supplementation
versus placebo on the lipid profile and high-sensitivity
C-reactive protein (hsCRP) levels. As seen, compared to
placebo, only the AC952 regular Aloe vera inner leaf gel
powder preparation resulted in significant reduction on total
cholesterol and LDL-C levels. None of the other parameters
changed significantly.
With regard to parameters of insulin resistance and dys-
glycemia, which are reported in Table 3, in the UP780 Aloe
vera inner leaf gel powder standardized with 2% aloesin
group, there were significant reductions in HbA1c as well as
in fructosamine levels, indicators of glycemic control. While
fasting blood glucose was significantly reduced, there were
no changes in the AUC of glucose values obtained from the
2-h OGTT. Also, insulin levels were significantly decreased.
Thus, in the UP780 group, there was significant reduction in
homeostasis model assessment (HOMA), a marker of insulin
sensitivity (Fig. 1). In the AC952 aloe group, in addition to a
decrease in fructosamine, there were significant reductions in
glucose values after supplementation. There were no chan-
ges in the urinary microalbumin:creatinine ratios in any of
the groups.
Because aloe has been shown to improve oxidative stress
in diabetic rats and because oxidative stress can contribute to
diabetic complications, we tested the effect of two Aloe vera
supplementations on a prototypic biomarker of lipid oxida-
tion, urinary F2-isoprostanes. As seen in Fig. 2, only the
UP780 aloe group showed a significant reduction in the F2-
isoprostanes; the reduction in the AC952 group was not
significantly different compared to placebo.
Discussion
The metabolic syndrome is highly prevalent worldwide
and is associated with a greater risk of atherosclerotic
cardiovascular disease than any of its individual compo-
nents and leads to a five-fold increase in diabetes and a
two-fold increase in cardiovascular disease.
1–3
The primary
target of treatment of patients with metabolic syndrome is
therapeutic lifestyle changes, which are difficult to achieve
and, thus, any adjunctive measures to reduce the burden
of diabetes and cardiovascular disease in this population
are welcome.
1–3
Numerous animal trials have reported positive effects
of Aloe vera in rat models of diabetes; however, there are
very few clinical trials in humans.
4–11
There are several
Table 2. Effect of Aloe vera Supplementation on the Lipid Profile and hsCRP
Placebo Placebo UP780 UP780 AC952 AC952
Week 0 Week 8 Week 0 Week 8 Week 0 Week 8
Total cholesterol (mg/dL) 196 31 200 28 210 27 213 27 206 29 186 29**
Triglycerides (mg/dL) 121.4 63.2 140 79 146 121 158 114 156 87 148 80
HDL-C (mg/dL) 42 17 42.1 13.8 49 17 44 15 40 10 38 10
LDL-C (mg/dL) 129.5 22.1 130.6 19.8 135 25 138 29 135 26 118 24**
hsCRP (mg/L) 3.05 3.65 1.6 2.05 2.7 3.8
Data are provided as mean standard deviation (SD) except hsCRP, for which the median is provided.
**P<0.05 compared to placebo and baseline.
hsCRP, high-sensitivity C-reactive protein; HDL-C, high-density lipoprotein; LDL-C, low-density lipoprotein.
Table 3. Effect of Aloe vera Supplementation on Parameters of Glycemia and Insulin Resistance
Placebo Placebo UP780 UP780 AC952 AC952
Week 0 Week 8 Week 0 Week 8 Week 0 Week 8
HbA1c(%) 5.8 0.58 5.8 0.56 6.0 0.66 5.7 0.6* 6.0 0.5 5.9 0.5
Glucose (mg/dL) 105 13 108 15 111 15 103 16* 111 11 105 12**
AUC Glu-OGTT 274 51 279 63 317 83 313 93 327 51 322 63
Microalbumin:creatinine ratio 8.1 12.6 6.6 6.3 6.6 3.8 7.1 10 15.3 27.9 7.2 4.3
Fructosamine (ng/mL) 3.1 1.5 2.9 1.4 3.0 1.0 2.3 0.63* 2.83 1.12 2.40 1.4**
Insulin (mIU/mL) 19.9 8.0 20.9 11 16 11 12 8* 18.6 14 16.1 9
Data are provided as mean standard deviation (SD).
*p<0.02 and **p<0.05 compared to placebo and baseline.
HbA1c, glycosylated hemoglobin; AUC, area under the curve; Glu-OGTT, glucose tolerance.
ALOE SUPPLEMENTATION AND METABOLIC SYNDROME 3
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anecdotal reports of antidiabetic activity of aloe in hu-
mans,
12,13
but there is a paucity of controlled clinical tri-
als.Thus,inthispilotstudy,wewishedtotesttheeffect
of two aloe products in a double-blind, randomized, pla-
cebo-controlled study. The results from our pilot study
show that among the two aloe supplements, UP780 was
more effective in affecting parameters of insulin sensitiv-
ity, such as the fasting glucose, fructosamine, HbA1c,
HOMA, and insulin. AC952 was effective in lowering
LDL-C, fasting blood glucose, and fructosamine. Also,
UP780 reduced a marker of whole body oxidation, urinary
F2-isoprostanes.
FIG. 1. Effect of Aloe vera
supplementation on homeo-
stasis model assessment
(HOMA). Fasting glucose and
insulin levels were measured
and HOMA calculated in pa-
tients before and after placebo,
UP780, or AC952 supplemen-
tation. (*) P<0.05 compared to
placebo and baseline.
FIG. 2. Effect of Aloe vera
supplementation on urinary
F2-isoprostanes. Urinary F2-
isoprstane levels were as-
sessed and normalized to
urinary creatinine in patients
before and after placebo,
UP780, or AC952 supplemen-
tation. (*) P<0.05 compared to
placebo and baseline.
4 DEVARAJ ET AL.
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UP780 (aloe product 1) consists of aloe gel fillet powder
(the inner gel fillet that remains after removal of the outer
rind of the leaf), standardized with 2% aloesin by weight,
using aloe chromones and other biologically active compo-
nents that may be important in maintenance of normal blood
glucose levels. Qmatrix or AC 952 (aloe product 2) is aloe gel
fillet powder (without aloesin) standardized to a minimum
of 10% polysaccharide by weight. It is currently on the
market and in use in the finished products of approximately
100 companies, including dietary supplements and other
ingestible products; however, its effects have not been pre-
viously tested with regard to its antiglycemic effects in a
placebo-controlled study.
With regard to hypoglycemic effects, several reports
agree with ours with regard to effects in diabetic mice and
rat models.
4–11
There is a single placebo-controlled study
in the literature in hyperlipidemic type 2 diabetic pa-
tients
14
that showed the benefit of aloe in reducing the
burden of diabetes; however, all of the subjects were al-
ready on one or two diabetic medications and aloe was
given in conjunction with these. Thus, this is the first study
showing that even in patients with impaired fasting glu-
cose or impaired glucose tolerance, an 8-week supple-
mentation with Aloe vera gel powder with 2% aloe
chromone (UP780) is effective in reducing fasting glucose,
fructosamine,HbA1c,andHOMA,amarkerofinsulin
resistance. It is not surprising that UP780 did not lower
cholesterol levels, because previous reports regarding hy-
polipidemic effects of aloe are contradictory. In fact, while
acemannan, an active ingredient in the Aloe vera gel, is
thought to be responsible for the hypoglycemic effect of
aloe, no active ingredient has previously been isolated to
explain its hypolipidemic effects.
Oxidative stress plays a critical role in metabolic syn-
drome and diabetes.
15,16
F2-isoprostanes are biomarkers of
whole-body lipid oxidation, which have been shown to be
increased in diabetes.
17
We show that UP780 aloe supple-
mentation significantly decreased F2-isoprostanes. In sup-
port of our observations, Rajasekaran et al. have previously
reported that oral administration of an alcoholic extract of
Aloe vera leaf gel at a concentration of 300 mg/kg to diabetic
rats, in addition to improving glycemic control, significantly
decreased the levels of lipid peroxidation and hydroperox-
ides in tissues of diabetic rats and also resulted in a signifi-
cant increase in reduced glutathione, superoxide dismutase,
catalase, glutathione peroxidase, and glutathione S-transferase
in the liver and kidney of diabetic rats.
18
Because UP780 is a standardized Aloe vera gel preparation,
these exciting effects of its hypoglycemic activity as well as
lowering of lipid oxidation are promising, especially due to
the excellent safety profile and compliance. Thus, such
standardized aloe preparations offer an attractive adjunctive
strategy to revert the impaired fasting glucose and impaired
glucose tolerance observed in conditions of prediabetes/
metabolic syndrome and need to be tested in multicenter
clinical trials. Future studies will also examine the active
ingredient in aloe that is responsible for these effects and
examine mechanisms to elucidate these findings.
Acknowledgment
Unigen Inc., AloeCorp., for financial support and aloe
products and placebo.
Author Disclosure Statement
S.D received a grant from Unigen and MY, LAB, QJ are
employed at Unigen.
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Address correspondence to:
Sridevi Devaraj, Ph.D., DABCC, FACB
Medical Director of Clinical Chemistry and POCT
Texas Children’s Hospital
Professor of Pathology and Immunology
Baylor College of Medicine
Director of Proteomic and Metabolomics Core
Texas Children’s Microbiome Center
6621 Fannin Street, Suite WB110.06
Houston, TX 77030
E-mail: sxdevara@texaschildrens.org
6 DEVARAJ ET AL.
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... Aloe vera (L.) Burm.f extracts significantly reduced fasting blood glucose in diabetic and prediabetic patients (Devaraj et al., 2013;Alinejad-Mofrad et al., 2015). ...
... A clinical trial of Aloe vera (L.) Burm.f. products (UP780 and AC952) in patients with prediabetes/metabolic syndrome showed that the formulations can reverse the abnormalities in fasting glucose and improve glucose tolerance of the subjects (Devaraj et al., 2013). These clinical studies provide significant evidence that show the potential of Aloe vera (L.) Burm.f. ...
Full-text available
Article
Use of medicinal plants and herbs in the treatment and management of diseases, including diabetes mellitus and its complications remains an integral part of African tradition. In Zimbabwe, nearly one million people are living with diabetes mellitus. The prevalence of diabetes mellitus in Zimbabwe is increasing every year due to lifestyle changes, and has accelerated the use of traditional medicines for its treatment and management in urban areas. In addition, the high cost of modern medicine has led many people in rural parts of Zimbabwe to rely on herbal plant medicine for the treatment of diabetes mellitus and its complications. This review highlights a number of studies carried out to evaluate the antidiabetic properties of indigenous plants found in Zimbabwe with the goal of treating diabetes mellitus. Further, we discuss the mechanism of action of various plant extracts in the treatment and management of diabetes mellitus. Together, this review article can open pathways leading to discovery of new plant derived medicines and regularization of use of crude plant remedies to treat diabetes mellitus by the Zimbabwean government and others across Africa.
... Studies have shown that A. vera lowers the blood sugar level due to its increased metabolism, while leaving the normal blood lipid level and liver/ kidney function intact (Hamman 2008;Huseini et al. 2012). Devaraj et al. (2013) delineated that A. vera impacts diabetes through reducing the body weight and enhancing insulin (Devaraj et al. 2013). In addition, A. vera gel could positively impact diabetic patients due to its antioxidant properties (Yongchaiyudha et al. 1996;Jain et al. 2010). ...
... Studies have shown that A. vera lowers the blood sugar level due to its increased metabolism, while leaving the normal blood lipid level and liver/ kidney function intact (Hamman 2008;Huseini et al. 2012). Devaraj et al. (2013) delineated that A. vera impacts diabetes through reducing the body weight and enhancing insulin (Devaraj et al. 2013). In addition, A. vera gel could positively impact diabetic patients due to its antioxidant properties (Yongchaiyudha et al. 1996;Jain et al. 2010). ...
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Diabetes mellitus is defined as prolonged hyperglycemia, which can harm the eyes, kidneys, and cardiovascular and neurological systems. Herbal agents and their derived supplements have been used for treatment of diabetes mellitus as a part of integrated complementary medicine for centuries. Numerous studies have considered Aloe vera (L.) Burm.f, Xanthorrhoeaceae, as an alternative medicine due to its abundant bioactive chemicals, such as alkaloids, anthraquinones, and enthrones, with therapeutical properties including antioxidant, anti-inflammatory, neuro-protective, and anti-diabetic effects. Aloe vera has received considerable attention in traditional medicine for the treatment of several diseases including diabetes mellitus. Numerous studies have investigated the effects of herbal agents on diabetes mellitus using a streptozotocin-induced diabetic model. Thereby, this article reviews the effects of Aloe vera prescription on streptozotocin-induced diabetes mellitus to provide a clear insight into the role of this medicinal plant in several biological functions, such as antioxidant, wound healing, anti-inflammatory, anti-hyperglycemic, and anti-hyperlipidemic in diabetic models. Graphical abstract
... Few studies reported a rise in blood sugar after Aloe vera consumption (Koo, 1994). Moreover, some studies showed there was not any significant difference in blood glucose level and lipid profile comparing intervention and placebo groups (Zarrintan et al., 2015;Devaraj et al., 2013). Choudhary et al. (2014) stated that consumption of both 100 and 200 mg of Aloe vera powder can decrease the LDL, TC, TG, blood glucose and increase the HDL significantly. ...
... Several anthraquinones which include emodin, phytosterols, carbohydrates, including acetylated mannan (acemannan), enzymes, vitamins (B1, B2, B6, C, b -carotene, choline, folic acid, a-tocopherol), amino acids and proteins are present in Aloe vera (Hamman, 2008). Acemannan is thought to be responsible for the hypoglycemic effect of Aloe vera (Devaraj et al., 2013). Aloe vera also contains other compounds such as hydrophilic fiber, glucomannan and phytosterol that reduce blood glucose (Alinejad-Mofrad et al., 2015). ...
Article
Purpose It is well accepted that diabetes is associated with heart diseases and hyperlipidemia as a risk factor. In traditional medicines, some herbs such as Aloe vera seem to be effective in controlling diabetes. Owing to lack of human studies, this study aims to examine the effect of Aloe vera consumption on fasting blood sugar (FBS), lipid profiles and body composition in type 2 diabetic patients. Design/methodology/approach This double-blind, placebo-controlled trial study was conducted in 2019, in Shiraz, Iran. A total of 56 diabetic subjects were randomized by block randomization to receive a daily supplement of 1,000 mg Aloe vera powder capsules ( n = 28) or placebo ( n = 28) for eight weeks. At baseline and after eight weeks of treatment, dietary intake and physical activity were assessed by three-day food recall and international physical activity questionnaire. Meanwhile, after an overnight fasting, FBS and lipid profiles were measured. Blood pressure and anthropometric parameters were assessed in the beginning and the end of the study. Independent t -tests were used for between-group analysis and paired t -tests for within-group analysis. Findings After intervention, weight, body mass index and waist circumference significantly decreased in comparison to the placebo group ( p -value: < 0.001, 0.001 and 0.02). Although, FBS, total triglyceride and systolic blood pressure decreased significantly ( p -value: 0.03, 0.001 and 0.01), no change has been seen in low density lipoprotein, high density lipoprotein and total cholesterol blood level and diastolic blood pressure. Research limitations/implications The limitations of this study are the short study duration and lack of Aloe vera powder’s ingredient analysis. Originality/value This study is one of few human studies investigating the effect of Aloe vera on metabolic syndrome’s indices in diabetic patients. Because pharmacological therapy is tough, not comfort and correlated with potential adverse drug interactions, it is important to find an alternative or complementary measure to aid the diabetic patients. This study shows that Aloe vera has positive effect on body weight and blood sugar.
... They detected a significant decrease in the levels of fasting blood glucose and HbA1C in the treatment group. 23 Due to the unavailability of the data related to the effect of Aloe-based drink on the levels of GA and HOMA-IR values on MetS subjects, this study aims to investigate the effect of Aloe-based drink on the levels of GA and insulin resistance expressed by HOMA-IR values in MetS. ...
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Article
Insulin resistance (IR) has an important role in the pathology that forms the metabolic syndrome (MetS). Glycated Albumin (GA) has a role as an index of glycemic control associated with MetS. Aloe vera (Aloe barbadensis Miller) is a plant that has anti-diabetic and anti-hypercholesterolemic function. This study aims to investigate the effect of Aloe-based drink on GA and IR in MetS. This study was a true experimental using pre-post randomized control group design. Thirty-eight MetS subjects were divided into two groups: treatment group (n=19) which was provided by 165 g/d of Aloe-based drink for 4 weeks; and the control group (n=19). Both groups were given education regarding of management of MetS. GA was measured by using an ELISA method and IR calculated by HOMA-IR of both groups and statistically analyzed at baseline and the end of treatment. The data were analyzed using paired t-test and independent t-test. At the end of the study, the treatment group showed reduction of GA and HOMA-IR statistically significant (∆GA=-4.3±2.35%; p<0.001; ∆HOMA-IR=-1.6 ±1.87; p=0.001). Compared to control group, the change of GA and HOMA-IR in intervention group were also significantly different (p<0.001; p<0.001). Aloe-based drink was proven to reduce GA and IR in the MetS.
... In a related study, A. vera high molecular weight fraction (HMW) administered to type 2 diabetic subjects for 12 weeks significantly reduced the fasting blood glucose from 235.10 to 152.30 mg/dL and HbA1c from 7.90 to 6.30% (Yagi et al., 2009). The 8-week administration of two products made from A. vera gel also caused a reduction in the blood glucose, HbA1c, fructosamine and insulin concentration (Devaraj et al., 2013). ...
Article
Of all medicinal plants used to treat ailments, the genus Aloe represents one of the commonest. They manage various pathological conditions, including inflammation, infection, cancer and diabetes mellitus. There are specific reports on the hypoglycemic and antidiabetic potential of different species of Aloe. Still, there is a shortage of comprehensive reports which present all Aloe species with antidiabetic properties. This study aims to integrate available information on all Aloe spp. with antidiabetic potentials. Scientific databases such as PubMed, EBSCOhost, Science Direct, Scopus, and Google Scholar, were utilized to search and collect literature for this review. This review revealed that the most common Aloe sp. with antidiabetic potentials is A. vera. It also showed that few studies were carried out in vitro while most were performed in vivo. We can conclude that Aloe spp. is a potent source of antidiabetic agents. Further studies should be conducted to isolate the antidiabetic compounds from the plant.
... Powder and aqueous extract of bitter melon fruit are effective in lowering HbA1c significantly [43,44]. Results of the present study were closely related to the findings of Devaraj et al., 2013; Alinejad-Mofrad et al., 2015, as they showed that the supplementation of aloe vera gel was responsible for the reduction of HbA1c in type II diabetes patients but showed no significant effect in pre-diabetics. ...
Article
Background: Diabetes mellitus is 4th leading cause of death worldwide. Diet based approaches to treat various health disorders are considered safe, economical and sustainable. Complementary and alternative medicine (CAM) is one of the methods used worldwide for the management of diabetes millets. Momordica charantia and Aloe barbadensis both are known for their medicinal potential including antidiabetic, anti-inflammatory and anti-oxidant properties. Objective: The present study was designed to achieve following objectives: to analyze bitter melon seed (BMS) and aloe vera gel (AVG) powder for proximate and mineral content; to develop functional chicken nuggets by using various concentrations of both powdered and their compositional analyses and to probe the antidiabetic potential of powders in synergy. Design: A control and two formulations were selected, based on consumer acceptability, for efficacy trial through the animal model of 30 days. For this purpose, 18 diabetic Sprague Dawley Rats were randomly divided into 3 groups. The groups included the positive control group (G0, normal diet) and two other groups with different AVG and BMS powder. G1 group received 50% BMS and 50% AVG powder whereas, G2 was feed on 75% BMS and 25% AVG powder per day. Results: G1 showed a significant reduction in fasting blood glucose level, glycated haemoglobin, cholesterol, LDL-Cholesterol, blood urea nitrogen and uric acid, whereas the G2 showed improvement in insulin, HDL-Cholesterol and triglycerides levels whereas showed better control over time. Conclusion: Supplementation of BMS and AVG can help to control hyperglycemia and related complications.
... [25] Another research on human patients, conducted in hospitals in India in 2008, showed that only two aloe capsules (500 mg each), administered daily, stop the evolution of type II diabetes. [26] Comparative description of patients with obesity treated with placebo (before and after). The dried latex of the aloe plant (aloes) is one of several traditional remedies used for diabetes in the Arabian Peninsula. ...
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Background: Aloe ferox is one of the most widely used medicinal plants today, with the most intense detoxifying action of all aloe species, being used in the treatment of various diseases, including obesity. Our study aimed to assess the efficacy of Aloe ferox in obesity treatment. Methods: The study sample included 20 Romanian persons with obesity treated with diet and Aloe ferox based supplements, and 20 Romanian matched controls treated with diet and a placebo. The treatment included 2 capsules/day (Aloe ferox 460 mg) for 2 weeks, followed by a 2-week break, repeated 3 times. The blood pressure (systolic and diastolic) and anthropometric parameters, such as body mass index (BMI), total cholesterol, and abdominal circumference, as well as the biochemical parameters, fasting blood glucose (FBG), uric acid, and lipid profile was evaluated at baseline and after 3 months. Results: After 3 months of Aloe ferox administration, significant differences between the study group and the control group were observed regarding BMI (P = .03), total cholesterol (P = .032), low-density lipoprotein cholesterol (LDLc) (P = .01) and FBG (P = .018). Also, between the initial clinical, anthropometric, and biological parameters and those after the administration of Aloe ferox in the study group, we obtained significant differences regarding BMI (P = .002), LDLc (P = .039), fasting glycemia (P < .001) and diastolic blood pressure (P = .006). Conclusions: The administration of Aloe ferox to obese patients has been shown to achieve a significant reduction in body weight, BMI, LDLc, and FBG. These effects may be due to the laxative and detoxifying action of Aloe ferox components. As it can only be administered for limited periods due to side effects, further experimental and human studies of the efficacy of this plant in the treatment of obesity are needed.
... conducted to evaluate the effects of this herb on diabetes mellitus and blood glucose level. 20 Many studies have shown that Aloe vera extract can decrease blood glucose level; [21][22][23][24] for example in a study done by Tanaka M et al on diabetic and non diabetic mice, it is demonstrated that Aloe vera extract can reduce blood glucose level. 25 As many studies revealed positive effect of Aloe vera extract on blood glucose level and lipid profile markers in diabetic patients, many other studies have shown that administrating Aloe vera in diabetic patients reduces the micro vascular and macro vascular complications of this metabolic disease such as healing diabetic wound, eliminating diabetic nephropathy and retinopathy, decreasing the risk of cardiovascular complications etc. [26][27][28][29][30][31][32] As there is a controversy in effect of Aloe vera extract on diabetes mellitus disease and its effect on blood glucose level in DM patients and also most of the studies in this regard have been conducted on animal samples, in this study we are aimed to evaluate the effect of Aloe vera supplements on blood glucose level and lipid profile of patients with type 2 DM. ...
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Background: One of the most studied methods to adjust the blood glucose level and dyslipidemia in diabetic patients is administrating of herbal supplements. This double blinded randomized clinical trial (RCT) study we are aimed to study the effect of Aloe vera supplements on blood glucose level and lipid profile of diabetes mellitus type 2 patients. Methods: 44 patients (25 male and 19 female) fulfilling inclusion criteria, were divided into two groups of intervention and placebo randomly. The patients in intervention group received 1000 mg of Aloe vera supplements and the patients of placebo group received placebo, daily for two months beside the main treatment for diabetes mellitus. Before and after the intervention blood samples were taken from all the patients; and were measured for blood glucose level and lipid profile. The data were analyzed using independent T-test method. This RCT study was submitted in IRCT center by submitted code of IRCT201307269626N3. Results: The results revealed that the levels of the fasting blood sugar (FBS), HbA1c, Total Cholesterol, Triglyceride, high density lipoprotein (HDL), low density lipoprotein (LDL) were not significantly different between the pre-intervention and post intervention blood samples in both intervention and placebo group. Also there was not any significant difference in blood glucose level and lipid profile comparing intervention and placebo groups. Conclusion: In this study, we can conclude that Aloe vera supplement beside the main treatment for diabetes mellitus has no significant effect in blood glucose level and lipid profile in diabetes mellitus type 2 patients.
Article
Dyslipidemia is a common feature of type 2 diabetes mellitus and is characterised by elevated triglyceride, decreased HDL cholesterol, and increased small dense LDL cholesterol levels. The underlying causes appears to be associated with insulin resistance, increased free fatty acid reflux, and low-grade inflammation, resulting in increased hepatic lipogenesis, and altered lipoprotein metabolism. Improved glycaemic control has been shown to have a positive effect on lipoprotein levels in diabetics. This can be achieved through medications/therapeutics and life style changes. Several classes of pharmacologic agents are currently in use to treat dyslipidemia. However, they may have dangerous long-term side effects, including an increased risk of liver dysfunction, weight gain, and cardiovascular diseases. Therefore, stronger alternatives with fewer side effects are required to reduce the diabetes associated complications. Many secondary plant metabolites have been shown to improve glucose homeostasis and lower lipid levels. Aloe vera and its constituents have long been used in a traditional medicine system for a diverse range of biological activities, including hypoglycaemic, antioxidant, anticarcinogenic, anti-inflammatory, and wound healing effects through various mechanisms and they have been covered well in literature. However, studies on the potential role of Aloe vera in the treatment of diabetic dyslipidemia are scanty. Therefore, in this systematic review, we focussed on the potential effect of Aloe vera and its active components in alleviating diabetic dyslipidemia, as well as their mechanism of action in pre-clinical and clinical studies.
Article
Background: Diabetes mellitus (DM) is a metabolic disease of the endocrine system, characterized by chronic hyperglycemia, resulting either from insulin resistance or defective insulin production due to dysfunction of pancreatic β-cells. Approximately 80% of diabetic patients live in developing and underdeveloped countries. Pakistan is ranked on 7th position regarding the prevalence of DM. In developed nations, DM is the 4th leading reason for death. Several conventional and traditional methods i.e., allopathic medicines, herbal and medical plants have being used to treat DM and its complications for several decades. Diet-based approaches are considered safe, economical, and sustainable by individuals suffering from various health disorders. Objectives: The current review has been generated to highlight and compare the utilization of various conventional and traditional methods i.e., allopathic medicines, herbal and medical plants as an alternative source to treat DM and its complications. Methodology: Existing relevant literature (both research / review articles) published in last many years was looked over numerous sources like Google Scholar, Medline, PubMed, Research Gate, Science Direct, Scopus and Web of Science. Results: Complementary and Alternative Medicine (CAM) is considered a holistic approach for the treatment of Diabetes that combines the use of dietary supplements with herbs. Worldwide, approximately 30% of DM patients and 50% in Pakistan are using CAM. Aloe vera (AV) is known as a “miracle plant” and extensively used in commercial products. AV contains numerous bioactive components such as vitamins, saponins, salicylic acid, minerals, lignin, enzymes, anthraquinones, and amino acids which are responsible for healthpromoting activities in the body. Isolated bioactive components have extensively been employed in nutraceuticals and pharmaceutical items and claimed to have antioxidant potential. Phytosterol compounds such as phenol and cycloartenol have claimed to downregulate the synthesis of fatty acid and increases the oxidation in the liver that in results decrease in lipid deposition. Conclusion: From the above analysis, it is therefore concluded that the utilization of herbaceous plants as medicine can be encouraged to treat and prevent numerous health problems.
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Significant degenerative changes were observed in the kidney tissue of untreated neonatal streptozotocin (n0STZ)-induced type-II diabetic rats. These degenerative changes were diminished in the kidney tissue of diabetic animals given glibenclamide and Aloe leaf gel and pulp extracts. Kidney lipid peroxidation levels were increased in diabetic rats compared to healthy rats; these levels were higher in rats treated with glibenclamide than in those which received Aloe extracts. Serum urea and creatinine levels were higher in diabetic rats in comparison to healthy rats. The administration of Aloe gel extract and glibenclamide decreased serum urea and creatinine levels in comparison to diabetic controls. Only A. vera leaf gel extract showed improvement both in histological and biochemical parameters suggesting a protective effect of A. vera on mild damage caused by type-II diabetes on kidney tissue.
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Diabetes mellitus type 2 with dyslipidemia is a common disease. Previous studies suggest that aloe (Aloe vera L.) leaf gel may positively affect the blood glucose and lipid levels in dyslipidemic type 2 diabetic patients. Thus, in this randomized double-blind placebo-controlled clinical trial with hyperlipidemic (hypercholesterolemic and/or hypertriglyceridemic) type 2 diabetic patients aged 40 to 60 years not using other anti-hyperlipidemic agents and resistant to daily intake of two 5 mg glyburide tablets and two 500 mg metformin tablets, the efficacy and safety of taking aloe gel (one 300 mg capsule every 12 hours for 2 months) combined with the aforementioned drugs in treatment of 30 patients were evaluated and compared with the placebo group (n = 30). The aloe gel lowered the fasting blood glucose, HbA1c, total cholesterol, and LDL levels significantly (p = 0.036, p = 0.036, p = 0.006, and p = 0.004, respectively) without any significant effects on the other blood lipid levels and liver/kidney function tests (p > 0.05) compared with the placebo at the endpoint. No adverse effects were reported. The results suggest that aloe gel may be a safe anti-hyperglycemic and anti-hypercholesterolemic agent for hyperlipidemic type 2 diabetic patients.
Article
The diabetic state confers an increased propensity to accelerated atherogenesis. In addition to the established risk factors, there is evidence for increased oxidative stress in diabetes. Increased oxidative stress is manifested by increased lipid peroxidation, increased F 2 -isoprostanes, increased nitrotyrosine, and increased DNA damage. Also, in diabetics, there is increased superoxide release. With regard to diabetes, antioxidants such as α-tocopherol, α-lipoate, and ascorbic acid supplementation have been shown to be beneficial. Most importantly, α-tocopherol therapy, especially at high doses, clearly shows a benefit with regard to low-density lipoprotein oxidation, isoprostanes, and monocyte superoxide release. Thus, it appears that, in diabetes, antioxidant therapy could alleviate the increased attendant oxidative stress and emerge as an additional therapeutic modality.
Article
The effect of Aloe vera juice in combination with glibenclamide was investigated in diabetic patients. There was no response to glibenclamide alone but Aloe vera juice significantly reduced levels of fasting blood glucose within two weeks and of triglycerides within four weeks. It showed no effect on cholesterol levels and had no toxic effects on kidney or liver function as assessed by blood chemistry. The results support the use of Aloe vera in the treatment of diabetes.
Article
Aloe vera gel has been claimed to have antidiabetic activity but not all published results are consistent. We investigated the effect of oral administration of one tablespoonful of Aloe vera juice, twice a day for at least 2 weeks in patients with diabetes. Blood sugar and triglyceride levels in the treated group fell; cholesterol levels were not affected. The results suggest the potential of aloe vera juice for use as an antidiabetic agent.
Article
Pre-diabetes represents an elevation of plasma glucose above the normal range but below that of clinical diabetes. Pre-diabetes can be identified as either impaired fasting glucose (IFG) or impaired glucose tolerance (IGT). The latter is detected by oral glucose tolerance testing. Both IFG and IGT are risk factors for type 2 diabetes, and risk is even greater when IFG and IGT occur together. Pre-diabetes commonly associates with the metabolic syndrome. Both in turn are closely associated with obesity. The mechanisms whereby obesity predisposes to pre-diabetes and metabolic syndrome are incompletely understood but likely have a common metabolic soil. Insulin resistance is a common factor; systemic inflammation engendered by obesity may be another. Pre-diabetes has only a minor impact on microvascular disease; glucose-lowering drugs can delay conversion to diabetes, but whether in the long run the drug approach will delay development of microvascular disease is in dispute. To date, the drug approach to prevention of microvascular disease starting with pre-diabetes has not been evaluated. Pre-diabetes carries some predictive power for macrovascular disease, but most of this association appears to be mediated through the metabolic syndrome. The preferred clinical approach to cardiovascular prevention is to treat all the metabolic risk factors. For both pre-diabetes and metabolic syndrome, the desirable approach is lifestyle intervention, especially weight reduction and physical activity. When drug therapy is contemplated and when the metabolic syndrome is present, the primary consideration is prevention of cardiovascular disease. The major targets are elevations of cholesterol and blood pressure.
Article
A cluster of risk factors for cardiovascular disease and type 2 diabetes mellitus, which occur together more often than by chance alone, have become known as the metabolic syndrome. The risk factors include raised blood pressure, dyslipidemia (raised triglycerides and lowered high-density lipoprotein cholesterol), raised fasting glucose, and central obesity. Various diagnostic criteria have been proposed by different organizations over the past decade. Most recently, these have come from the International Diabetes Federation and the American Heart Association/National Heart, Lung, and Blood Institute. The main difference concerns the measure for central obesity, with this being an obligatory component in the International Diabetes Federation definition, lower than in the American Heart Association/National Heart, Lung, and Blood Institute criteria, and ethnic specific. The present article represents the outcome of a meeting between several major organizations in an attempt to unify criteria. It was agreed that there should not be an obligatory component, but that waist measurement would continue to be a useful preliminary screening tool. Three abnormal findings out of 5 would qualify a person for the metabolic syndrome. A single set of cut points would be used for all components except waist circumference, for which further work is required. In the interim, national or regional cut points for waist circumference can be used.