ArticlePDF Available

Nutrigenomic Studies of Effects of Chlorella on Subjects with High-Risk Factors for Lifestyle-Related Disease

Authors:

Abstract and Figures

In order to clarify the physiological effects of Chlorella intake on subjects with high-risk factors for lifestyle-related diseases, we conducted Chlorella ingestion tests on 17 subjects with high-risk factors for lifestyle-related diseases and 17 healthy subjects over a 16-week period, including a 4-week post-observation period. We conducted blood biochemical tests and analyzed gene expression profile in whole blood cells in the peripheral blood before and after Chlorella intake. We confirmed that in both groups, Chlorella intake resulted in noticeable reductions in body fat percentage, serum total cholesterol, and fasting blood glucose levels. Through gene expression analysis, we found that gene expression profiles varied with Chlorella intake and identified many genes that exhibited behavior such that after the completion of the intake period, expression levels returned to pre-intake expression ones. Among these were genes related to signal transduction molecules, metabolic enzymes, receptors, transporters, and cytokines. A difference in expression level was found between the two groups at the start of the tests, and we were able to identify genes with noticeable variance in expression level resulting from Chlorella intake in the high-risk factor group. These included genes involved in fat metabolism and insulin signaling pathways, which suggests that these pathways could be physiologically affected by Chlorella intake. There were clear variations in the expression profiles of genes directly related to uptake of glucose resulting from Chlorella intake, indicating that the activation of insulin signaling pathways could be the reason for the hypoglycemic effects of Chlorella.
Content may be subject to copyright.
JOURNAL OF MEDICINAL FOOD
J Med Food 11 (3) 2008, 395–404
© Mary Ann Liebert, Inc. and Korean Society of Food Science and Nutrition
DOI: 10.1089/jmf.2006.0180
Nutrigenomic Studies of Effects of Chlorella on Subjects with High-Risk Factors
for Lifestyle-Related Disease
Toru Mizoguchi,
1
Isao Takehara,
2
Tohru Masuzawa,
2
Toshiro Saito,
3
and Yo Naoki
1
1
Sun Chlorella Corporation, Kyoto;
2
New Drug Development Research Center, Inc., Hokkaido;
and
3
Life Science Group, Hitachi, Ltd., Saitama, Japan
ABSTRACT In order to clarify the physiological effects of Chlorella intake on subjects with high-risk factors for lifestyle-
related diseases, we conducted Chlorella ingestion tests on 17 subjects with high-risk factors for lifestyle-related diseases and
17 healthy subjects over a 16-week period, including a 4-week post-observation period. We conducted blood biochemical tests
and analyzed gene expression profile in whole blood cells in the peripheral blood before and after Chlorella intake. We con-
firmed that in both groups, Chlorella intake resulted in noticeable reductions in body fat percentage, serum total cholesterol,
and fasting blood glucose levels. Through gene expression analysis, we found that gene expression profiles varied with
Chlorella intake and identified many genes that exhibited behavior such that after the completion of the intake period, ex-
pression levels returned to pre-intake expression ones. Among these were genes related to signal transduction molecules, meta-
bolic enzymes, receptors, transporters, and cytokines. A difference in expression level was found between the two groups at
the start of the tests, and we were able to identify genes with noticeable variance in expression level resulting from Chlorella
intake in the high-risk factor group. These included genes involved in fat metabolism and insulin signaling pathways, which
suggests that these pathways could be physiologically affected by Chlorella intake. There were clear variations in the ex-
pression profiles of genes directly related to uptake of glucose resulting from Chlorella intake, indicating that the activation
of insulin signaling pathways could be the reason for the hypoglycemic effects of Chlorella.
KEY WORDS: hypocholesterolemic effect hypoglycemic effect insulin insulin signaling pathway gene ex-
pression microarray peripheral blood
395
INTRODUCTION
C
LORELLA HAS BEEN CONSUMED
by humans as a food sup-
plement for generations because it is rich in essential
nutrients, including high-quality protein, vitamins, minerals,
and essential amino acids. In recent years, it has gained at-
tention as a health food because it offers an outstanding bal-
ance of nutritional elements. Notably, it has been reported
that Chlorella demonstrates physiological effects such as
immune activation,
1
growth promotion,
2
and improvement
in stress-related ulcers.
3
Most of this prior research, how-
ever, used rats, mice, and other laboratory animals; almost
no large-scale clinical research has been undertaken to eval-
uate its physiological effects in humans.
The physiological effects of specific foods have long been
known empirically, but because foods are composed of di-
verse components, it has been difficult to identify the com-
ponents that are effective in bringing about desirable phys-
iological effects. At the same time, there has been little re-
search conducted on the mechanisms of these physiological
effects, because of the lack of effective testing and analyti-
cal methods that take into account multiple aspects of these
physiological effects. Amid a growing demand for health
foods in recent years, there have been calls for proof of the
effectiveness of these foods in humans, and for clarification
of the mechanisms involved. The term “evidence-based
food” is representative of this trend.
4
Since the announcement in 2004 that the entire human
genome sequence had been decoded, attention has been fo-
cused on a new research field called “nutrigenomics,” which
attempts to examine the utility of food products based on
genomic information.
5
Specifically, a DNA microarray that
can examine expression level of several thousand to several
tens of thousands of genes in a single assay has come to be
used extensively as a new tool for investigating diverse re-
actions in living organisms. This microarray technology is
extremely well suited to comprehensive examinations of
complex reactions in living organisms in which multiple
components bring about complex effects, as in the case when
food is ingested.
Manuscript received 25 September 2006. Revision accepted 6 March 2007.
Address reprint requests to: Toru Mizoguchi, Research and Development Department,
Sun Chlorella Corporation, Karasuma-dori, Gojo, Shimogyo-ku, Kyoto 600-8177, Japan,
E-mail: mizoguchi@sunchlorella.co.jp
In this research, we analyzed the gene expression profiles
in all peripheral blood cells following Chlorella intake in
17 subjects with high risk factors for lifestyle-related dis-
eases (diabetes or hyperlipemia) and 17 healthy subjects. We
also gathered biochemical test data from these subjects.
As a result of these tests, we confirmed that in both
groups, Chlorella intake resulted in noticeable reductions in
body fat percentage, total blood serum cholesterol, and fast-
ing blood glucose levels. Through gene expression analysis,
we found that gene expression varied with Chlorella intake
and identified many genes whose expression returned to pre-
intake expression levels after the completion of the intake
period. In the results for insulin signaling pathways in par-
ticular, variations were observed in the gene clusters directly
related to active uptake of glucose, which provides evidence
for the blood glucose reduction effects of Chlorella.
MATERIALS AND METHODS
Subjects
The subjects were healthy Japanese males 20 years of age
or older. On three occasions—6 weeks, 4 weeks, and 2
weeks—before the start of the ingestion tests, the subjects
were examined by a physician and also received physical
examinations, clinical examinations, and glucose tolerance
tests. Based on the conditions outlined below, 34 subjects
were selected, with 17 assigned to each of two groups: the
high-risk factor (for lifestyle-related diseases) group (re-
ferred to here as the “D Group”) and the normal healthy sub-
ject group (referred to here as the “N Group”).
Healthy subject group (N Group). At all three periods be-
fore beginning the tests, fasting blood glucose, total blood
serum cholesterol, and concentration of triglycerides in the
blood were within normal limits. These subjects were also
judged as having normal glucose tolerance.
High-risk factor group (D Group). Subjects who at all
three periods before beginning the tests (a) exhibited bor-
derline high fasting blood glucose and total blood serum
cholesterol and high triglycerides in blood and who were
also judged as having low glucose tolerance or (b) demon-
strated borderline high fasting blood glucose, were judged
as having low glucose tolerance, and were also judged to
have total blood serum cholesterol and serum triglycerides
that deviated slightly from normal limits. Attributes for sub-
jects in the N Group and D Group are summarized in Table
1. Serum was used for biochemical tests. Body fat percent-
age was evaluated by measuring bioelectrical impedance.
Materials tested
The Chlorella used in these tests was “Sun Chlorella A”
tablets (Sun Chlorella Corp., Kyoto, Japan), which contains
dried Chlorella powder (more than 95.5%) as the active in-
gredient and lecithin (less than 4.5%) as a bulking agent.
The Chlorella powder contained in the tablet was prepared
by crushing the cell wall in a DYNO
®
-Mill (WAB, Inc.,
Basel, Switzerland) and spray-drying. The subjects took 20
tablets each morning and evening (total, 40 tablets/day) af-
ter meals with either cold or hot water.
Test design
This research protocol was approved by the Testing Com-
mittee at Miyawaki Orthopedic Hospital (Hokkaido, Japan).
Before the tests began, the subjects received a written ex-
planation and consent form from the physicians responsible
for the tests. After receiving an explanation of the purpose
and value of the tests as well as the methods, expected ef-
fects, and potential risks, etc., the subjects themselves con-
firmed their understanding of the details explained and then
provided written consent indicating that they were partici-
pating of their own free will.
396 MIZOGUCHI ET AL.
T
ABLE
1. C
HARACTERISTICS OF
H
EALTHY AND
H
IGH
-R
ISK
S
UBJECT
G
ROUPS
Healthy subject group High-risk factor group
Characteristic (NGroup) (DGroup)
Age (years) 34.3 3.2 59.2 1.9
Height (cm) 170.7 1.6 164.5 1.3
Body weight (kg) 64.4 2.2 66.1 1.9
Body fat percentage 19.8 1.5 24.2 1.1
Body mass index (kg/m
2
) 21.8 2.2 24.4 2.1
Cholesterol (mg/dL)
Total 173.8 18.0 218.4 38.7
HDL 59.5 12.0 61.0 11.7
LDL 101.2 18.5 127.4 37.0
Triglycerides (mg/dL) 59.3 21.4 124.4 76.6
Fasting blood sugar (mg/dL) 82.4 7.2 111.4 30.1
Hemoglobin A1c (%) 4.5 0.2 5.3 0.8
Immunoreactive insulin (mU/mL) 5.0 3.1 6.1 4.0
Data are mean SD values.
The tests were conducted in an open test format. The in-
take period lasted for 12 weeks; blood biochemical tests
were conducted every 4 weeks, and again 4 weeks after the
completion of the intake period.
During the test period, one subject from the N Group
dropped out because of stomach pains, but no other subjects
dropped out during the testing period. Data for statistical
analysis were thus gathered for 17 subjects in the D Group
and 16 subjects in the N Group. None of the subjects in ei-
ther group reported any complications that could be con-
sidered to indicate harmful side effects during any of the
four physical examinations conducted during the testing
period.
Gene expression analysis
The blood sampling and RNA extraction for gene ex-
pression analysis was conducted using a PAXgene™ Blood
RNA kit (manufactured by PreAnalytiX GmbH, Hom-
brechtikon, Switzerland), and a model 2100 Bioanalyzer
(manufactured by Agilent Technologies, Palo Alto, CA) was
used to confirm that there was no breakdown in the extracted
RNA (rRNA profile used as a reference). RNA amplifica-
tion reactions were checked based on the in vitro transcrip-
tion method using primers with T7 promoter sequence. At
this time, cRNA was synthesized through the uptake of
dUTP with an aminoallyl group. The cRNA with Cy5 la-
NUTRIGENOMICS OF EFFECTS OF CHLORELLA 397
**
*
*
a
0w
60
N Group
FBS (mg/dL)
4w 8w 12w 16w
**
80 100 120 140 160 180 200
0w
D Group
4w 8w 12w 16w
*
b
0w
15
N Group
Body fat percentage (%)
4w 8w 12w 16w
**
20 25 30 35
0w
D Group
4w 8w 12w 16w
*
c
0w
N Group
T-Cho(mg/dL)
4w 8w 12w 16w
**
150 200 250
0w
D Group
4w 8w 12w 16w
d
0w
30
N Group
HDL-Cho (mg/dL)
4w 8w 12w 16w
**
40 50 60 70 80 90
0w
D Group
4w 8w 12w 16w
*
***
e
0w
50
N Group
LDL-Cho (mg/dL)
4w 8w 12w 16w
*
100 150 200
0w
D Group
4w 8w 12w 16w
*
**
*
FIG. 1. Time profile of (a) fasting blood glucose (FBS), (b) body
fat percentage, (c) total blood serum cholesterol (T-Cho), (d) HDL-
cholesterol (HDL-Cho), and (e) LDL-cholesterol (LDL-Cho) in the
healthy subject group (N Group) and the high-risk factor group (D
Group). The measured values before the start of Chlorella intake (0
weeks) and at each test point were tested for significant difference us-
ing paired ttests.
P5%.
beling was synthesized by applying coupling reactions to
cRNA and Cy5 with a succinimide group (manufactured by
GE Healthcare, Chalfont St. Giles, UK).
As the control sample for expression analysis, we used
total RNA from commercially available human white blood
cells (from Clontech Laboratories, Palo Alto), and Cy3 was
used as a fluorochrome. In addition, we synthesized cRNA
with the same labeling as the above blood-derived sample
and used this cRNA as a common comparative reference
sample for all blood-derived samples.
For the microarray, we used a custom microarray with
additional loading of diabetes-related genes and other
genes on a human drug response DNA chip (manufactured
by Hitachi Ltd., Saitama, Japan) (number of genes loaded,
1,873). After the labeled cRNA is mounted on the mi-
croarray, it is subject to competitive hybridization at 45°C
for 17 hours. Once hybridization is complete, the unit is
washed and dried, and fluorescent images are captured us-
ing a scanner (ScanArray5000, GSI Lumonics, Billerica,
MA). Through numerical processing, we then derived the
variable ratio for expression intensities between the sam-
ples and the reference samples for each of the relevant
genes. The global normalization method was used for nor-
malization of Cy5 and Cy3.
For expression data analysis, we used GeneSpring (Agi-
lent) and the R program package (R project; see http://www.
r-project.org/).
RESULTS
Blood analysis
Figure 1 shows changes over time in fasting blood glu-
cose, body fat percentage, total blood serum cholesterol,
high-density lipoprotein (HDL)-cholesterol, and low-density
lipoprotein (LDL)-cholesterol. Each of the measured values
shows decreasing trends after Chlorella intake and increas-
ing trends after completion of the intake test period (12
weeks). The measured values before the start of intake (0
weeks) and at each test point were tested for significance
using paired ttests. Using a significance level of 5%, both
the N Group and the D Group demonstrated significant dif-
ferences in body fat percentage and total blood serum cho-
lesterol from weeks 4 to 12. Particularly in the case of the
D Group, decreases in HDL-cholesterol and LDL-choles-
terol showed clearly significant differences at all measure-
ment points after the start of Chlorella intake. Blood glu-
cose levels were also significantly decreased in the D Group
after 8 weeks of chlorella consumption. In all of these mea-
sured values, a temporary decreasing trend could be seen af-
ter the start of Chlorella intake; after the completion of the
intake period, these values returned to the levels before in-
take began. This indicates that the variations in blood para-
meters were brought about as a result of Chlorella intake.
On the other hand, no clear variations in volumes of triglyc-
erides in the blood were observed before and after the start
of Chlorella intake in either the healthy subject group or the
high-risk factor group. Furthermore, no trends toward in-
creased concentration of insulin in the blood could be seen
as a result of Chlorella intake.
Based on the above data, we have summarized the effects
of Chlorella intake as follows. With regard to fat metabo-
lism, although no significant changes could be seen in the
concentration of triglycerides in the blood, both body fat
percentage and total serum cholesterol were decreased in
both the N and D Groups. With regard to glucose metabo-
lism, however, Chlorella lowered blood glucose in the D
Group. Since no clear increases in insulin concentrations in
the blood were observed, the decrease in serum glucose con-
centrations may be due to improved insulin sensitivity in-
duced by Chlorella intake.
Gene expression analysis
In both N and D Groups, we identified the genes whose
mRNA expression levels varied owing to Chlorella intake
by comparing expression intensities at 0 weeks (before the
start of intake tests) and 4 weeks and between 0 weeks and
12 weeks. Moreover, the genes whose mRNA expression
levels exhibited behavior consistent with the blood chem-
istry data, namely, gene expression profile varied with
Chlorella intake and then returned nearly to pre-intake ex-
pression levels, were extracted by comparison between ex-
pression change of 4 weeks versus 0 weeks and that of 16
weeks versus 0 weeks based on ttest. For these identifica-
tions, we used ttests with the False Discovery Rate 0.05
as the level of significance.
6
Next, the genes superimposed
in these two kinds of identified genes were extracted in both
the N and D Groups. A total of 129 genes were chosen, 66
of which are associated with canonical pathways in the
Kyoto Encyclopedia of Genes and Genomes (KEGG)
(http://www.genome.jp/kegg) database and are listed in
Table 2. Many kinds of genes involved in signal transduc-
tion, metabolism, receptors, transporters, and cytokines were
included. Moreover, this result suggested that many kinds
of pathways involved in the insulin signaling pathway and
immunological function may be influenced by Chlorella in-
take.
In the D Group, significant differences resulting from
Chlorella intake were observed for fasting blood glucose,
body fat percentage, and total serum cholesterol. In order to
identify the genes associated with these physiological ef-
fects, we extracted genes that demonstrated differences in
expression level between the D Group and the N Group be-
fore the start of the Chlorella intake tests and that also var-
ied as a result of Chlorella intake. Table 3 lists the 18 genes
thus identified. When we referred to the KEGG database to
determine which pathways the identified genes were asso-
ciated with, we found two genes (protein tyrosine phos-
phatase 1B and growth factor receptor-bound protein 2) that
are associated with the insulin signaling pathway. We then
investigated the changes in expressions for the genes among
the loaded genes that were associated with the insulin sig-
naling pathway. The results of this investigation are shown
398 MIZOGUCHI ET AL.
NUTRIGENOMICS OF EFFECTS OF CHLORELLA 399
T
ABLE
2. G
ENES
W
HOSE
E
XPRESSION
L
EVELS
V
ARIED WITH
C
HLORELLA
I
NTAKE AND
R
ETURNED TO
P
RE
-I
NTAKE
E
XPRESSION
V
ALUES
Target
accession Gene
number symbol Gene name Pathway name
NM_000208.1 INSR Insulin receptor Adherens junction, insulin signaling pathway, type 2 diabetes
mellitus, dentatorubropallidoluysian atrophy
Z69881.1 ATP2A3 ATPase, Ca
2
transporting, Calcium signaling pathway
ubiquitous
J03132.1 ICAM1 Intercellular adhesion molecule Cell adhesion molecules
1 (CD54), human rhinovirus
receptor
Y00062.1 PTPRC Protein tyrosine phosphatase, Cell adhesion molecules, T cell receptor signaling pathway
receptor type, C
NM_002592.1 PCNA Proliferating cell nuclear Cell cycle
antigen
M24898.1 NR1D1 Nuclear receptor subfamily 1, Circadian rhythm
group D, member 1
D89479.1 SULT1B1 Sulfotransferase family, Cysteine metabolism
cytosolic, 1B, member 1
D49950.1 IL18 Interleukin 18 (interferon- Cytokine–cytokine receptor interaction
gamma-inducing factor)
U37518.1 TNFSF10 Tumor necrosis factor (ligand) Cytokine–cytokine receptor interaction, apoptosis
superfamily, member 10
U01134.1 FLT1 Fms-related tyrosine kinase 1 Cytokine–cytokine receptor interaction, focal adhesion
(vascular endothelial growth
factor/vascular permeability
factor receptor)
M32977.1 VEGF Vascular endothelial growth Cytokine–cytokine receptor interaction, focal adhesion
factor
M65290.1 IL2B Interleukin 12B (natural killer Cytokine–cytokine receptor interaction, Toll-like receptor signaling
cell stimulatory factor 2, pathway, Jak-STAT signaling pathway
cytotoxic lymphocyte
maturation factor 2, p40)
D29013.1 POLB Polymerase (DNA directed), DNA polymerase
beta
U96132.1 HADH2 Hydroxyacyl-coenzyme A Fatty acid elongation in mitochondria, fatty acid metabolism,
dehydrogenase, type II valine, leucine, and isoleucine degradation, lysine degradation,
tryptophan metabolism, butanoate metabolism, caprolactam
degradation
NM_021187.1 CYP4F11 Cytochrome P450, family 4, Fatty acid metabolism, gamma-hexachlorocyclohexane
subfamily F, polypeptide 11 degradation, tryptophan metabolism
Y12863.1 FIGF c-fos-induced growth factor Focal adhesion
(vascular endothelial growth
factor D)
NM_030773.2 TUBB1 Tubulin, beta 1 Gap junction
J03746.1 MGST1 Microsomal glutathione S- Glutathione metabolism
transferase 1
NM_030821.3 PLA2G12A Phospholipase A2, group XIIA Glycerophospholipid metabolism, prostaglandin and leukotriene
metabolism, MAPK signaling pathway
V00572.1 PGK1 Phosphoglycerate kinase 1 Glycolysis/gluconeogenesis, carbon fixation
U79143.1 PIK3CA Phosphoinositide-3-kinase, Inositol phosphate metabolsim, phosphatidylinositol signaling
catalytic, alpha polypeptide system, apoptosis, focal adhesion, Toll-like receptor signaling
pathway, Jak-STAT signaling pathway, T cell receptor signaling
athway, B cell receptor signaling pathway, regulation of actin
cytoskeleton, insulin signaling pathway, type 2 diabetes mellitus
U92436.1 PTEN Phosphatase and tensin Inositol phosphate metabolism, phosphatidylinositol signaling
homolog (mutated in multiple system, focal adhesion, tight junction
advanced cancers 1)
NM_005399.3 PRKAB2 Protein kinase, AMP-activated, Insulin signaling pathway, adipocytokine signaling pathway
beta 2 noncatalytic subunit
AB003791.1 CHST1 Carbohydrate (keratan sulfate Keratan sulfate biosynthesis
Gal-6) sulfotransferase 1
(continued)
400 MIZOGUCHI ET AL.
U65928.1 COPS5 COP9 constitutive Lysine degradation, biotin metabolism
photomorphogenic homolog
subunit 5 (Arabidopsis)
U28014.1 CASP4 Caspase 4, apoptosis-related MAPK signaling pathway
cysteine protease
X03541.1 NTRK1 Neurotrophic tyrosine kinase, MAPK signaling pathway, apoptosis
receptor, type 1
U24153.1 PAK2 p21 (CDKN1A)-activated MAPK signaling pathway, axon guidance, focal adhesion, T cell
kinase 2 receptor signaling pathway, regulation of actin cytoskeleton
X63717.1 FAS Fas (tumor necrosis factor receptor MAPK signaling pathway, cytokine–cytokine receptor interaction,
superfamily, member 6) apoptosis
L13858.1 SOS2 son of sevenless homolog 2 MAPK signaling pathway, dorsoventral axis formation, focal
(Drosophila) adhesion, gap junction, Jak-STAT signaling pathway, T cell
receptor signaling pathway, regulation of actin cytoskeleton,
insulin signaling pathway
M22995.1 RAP1A RAP1A, member of the RAS MAPK signaling pathway, focal adhesion
oncogene family
X79483.1 MAPK12 MAPK 12 MAPK signaling pathway, Toll-like receptor signaling pathway
AF004709.1 MAPK13 MAPK 13 MAPK signaling pathway, Toll-like receptor signaling pathway
NM_000686.3 AGTR2 Angiotensin II receptor, type 2 Neuroactive ligand–receptor interaction
M18737.1 GZMA Granzyme A (granzyme 1, Neuroactive ligand–receptor interaction
cytotoxic T-lymphocyte-
associated serine esterase 3)
BC007720.1 HTR1D 5-Hydroxytryptamine Neuroactive ligand–receptor interaction
(serotonin) receptor 1D
AF000546.1 P2RY5 Purinergic receptor P2Y, G- Neuroactive ligand–receptor interaction
protein coupled, 5
U13699.1 CASP1 Caspase 1, apoptosis-related Neurodegenerative disorders, MAPK signaling pathway,
cysteine protease (interleukin Huntington’s disease, dentatorubropallidoluysian atrophy
1, beta, convertase)
NM_006312.1 NCOR2 Nuclear receptor co-repressor 2 Notch signaling pathway
NM_004718.2 COX7A2L Cytochrome coxidase subunit Oxidative phosphorylation
VIIa polypeptide 2-like
NM_004374.2 COX6C Cytochrome coxidase subunit Oxidative phosphorylation
VIc
NM_001865.2 COX7A2 Cytochrome coxidase subunit Oxidative phosphorylation
VIIa polypeptide 2 (liver)
L35249.1 ATP6V1B2 ATPase, H
transporting, Oxidative phosphorylation, ATP synthesis
lysosomal 56/58 kDa, V1
subunit B, isoform 2
Y15286.1 ATP6V0E ATPase, H
transporting, Oxidative phosphorylation, ATP synthesis, cholera
lysosomal 9 kDa, V0 subunit e
M62762.1 ATP6V0C ATPase, H
transporting, Oxidative phosphorylation, ATP synthesis, cholera
lysosomal 16 kDa, V0 subunit c
J05682.1 ATP6V1C1 ATPase, H
transporting, Oxidative phosphorylation, ATP synthesis, cholera
lysosomal 42 kDa, V1 subunit
C, isoform 1
NM_024330.1 SLC27A3 Solute carrier family 27 (fatty Propanoate metabolism, ethylbenzene degradation, limonene and
acid transporter), member 3 pinene degradation, caprolactam degradation, alkaloid biosynthesis
II
NM_003739.4 AKR1C3 Aldo-keto reductase family 1, Prostaglandin and leukotriene metabolism
member C3 (3-alpha
hydroxysteroid dehydrogenase,
type II)
NM_000895.1 LTA4H Leukotriene A4 hydrolase Prostaglandin and leuikotriene metabolism
NM_001116.1 ADCY9 Adenylate cyclase 9 Purine metabolism, calcium signaling pathway, gap junction
cholera
AF025840.1 POLE2 Polymerase (DNA directed), Purine metabolism, pyrimidine metabolism, DNA polymerase
epsilon 2 (p59 subunit)
T
ABLE
2. G
ENES
W
HOSE
E
XPRESSION
L
EVELS
V
ARIED WITH
C
HLORELLA
I
NTAKE AND
R
ETURNED TO
P
RE
-I
NTAKE
E
XPRESSION
V
ALUES
(C
ONT
D
)
Target
accession Gene
number symbol Gene name Pathway name
in Figure 2, which shows that after Chlorella intake, there
is an increase in expression levels for genes related to the
signal transduction routes linked to translocation of glucose
transporter (GLUT4) below the insulin receptors (produc-
ing insulin receptor substrate, phosphoinositide-3-kinase,
3-phosphoinositide-dependent kinase-1, and v-akt murine
thymoma viral oncogene homolog 3). Protein tyrosine phos-
phate-1B (PTP1B) acts to suppress signal transduction, but
the expression level for PTP1B showed a tendency to de-
crease as a result of Chlorella intake. Based on the changes
in gene expression levels, we can therefore surmise that in-
sulin signaling pathways are activated by the intake of
Chlorella. Recently, Cheng et al.
7
reported that in in vitro
screening systems using monocytes from human peripheral
blood, Chlorella inhibited the activation of PTP1B.
DISCUSSION
Cherng and Shih
8
reported changes in blood glucose con-
centrations resulting from administration of Chlorella in
streptozotocin-induced diabetic mice. In that study, they re-
ported that administration of Chlorella (100 mg/kg) steadily
reduced both glucose concentrations in the blood and in-
creased glucose values during glucose tolerance tests, but
that no increases in insulin concentrations in the blood could
be seen. Their results correspond closely with the results of
the current research on humans. It has also been reported
that in streptozotocin-diabetic mice, Chlorella intake in-
creases glucose uptake in the liver and skeletal muscles.
9
Dimitriadis et al.
10
reported that in monocyte in vitro sys-
tems separated from peripheral blood, insulin exposure
brought about an increase in the uptake of glucose and a
translocation of GLUT4 to the membrane surface. Estrada
et al.
11
reported that exposing peripheral blood monocytes
from healthy subjects and insulin-dependent diabetic pa-
tients to insulin-like growth factor-I immediately causes up-
take of glucose and that although the relationship of insulin-
like growth factor-I concentration and glucose uptake
volumes was similar in both healthy subjects and diabetes
patients, the cells obtained from diabetic patients demon-
strated lower uptake volumes overall. These recent investi-
gations also show that peripheral blood cells are an effec-
NUTRIGENOMICS OF EFFECTS OF CHLORELLA 401
T
ABLE
2. G
ENES
W
HOSE
E
XPRESSION
L
EVELS
V
ARIED WITH
C
HLORELLA
I
NTAKE AND
R
ETURNED TO
P
RE
-I
NTAKE
E
XPRESSION
V
ALUES
(C
ONT
D
)
Target
accession Gene
number symbol Gene name Pathway name
Z47727.1 POLR2K Polymerase (RNA) II (DNA Purine metabolism, pyrimidine metabolism, RNA polymerase
directed) polypeptide K, 7.0
kDa
X63563.1 POLR2B Polymerase (RNA) II (DNA Purine metabolism, pyrimidine metabolism, RNA polymerase
directed) polypeptide K, 140
kDa
J04965.1 POLR2E Polymerase (RNA) II (DNA Purine metabolism, pyrimidine metabolism, RNA polymerase
directed) polypeptide K, 25
kDa
U09178.1 DPYD Dihydropyrimidine Pyrimidine metabolism, beta-alanine metabolism, pantothenate and
dehydrogenase coenzyme A biosynthesis
NM_000436.2 OXCT1 3-Oxoacid coenzyme A transferase 1 Synthesis and degradation of ketone bodies, valine, leucine, and
isoleucine degradation, butanoate metabolism
U88878.1 TLR2 Toll-like receptor 2 Toll-like receptor signaling pathway
U88540.1 TLR1 Toll-like receptor 1 Toll-like receptor signaling pathway
NM_001752.2 CAT Catalase Tryptophan metabolism, methane metabolism, amyotrophic lateral
sclerosis
L34587.1 TCEB1 Transcription elongation factor Ubiquitin-mediated roteolysis
B (SIII), polypeptide 1 (15
kDa, elongin C)
NM_005438.2 FOSL1 FOS-like antigen 1 Wnt signaling pathway
NM_030775.2 WNT5B wingless-type mouse Wnt signaling pathway, hedgehog signaling pathway
mammary tumor virus
integration site family, member
5B
L37042.1 CSNK1A1 Casein kinase 1, apha 1 Wnt signaling pathway, hedgehog signaling pathway, gap junction,
circadian rhythm
NM_004422.1 DVL2 dishevelled, dsh homolog 2 Wnt signaling pathway, Notch signaling pathway
(Drosophila)
M74088.1 APC Adenomatosis polyposis coli Wnt signaling pathway, regulation of actin cytoskeleton
A total of 129 genes were extracted (see text) in this study. Among 129 genes, 66 genes that involved in canonical pathways summarized in
KEGG are listed. Jak-STAT, Janus kinase–signal transducers and activators of transduction; MAPK, mitogen-activated protein kinase.
402 MIZOGUCHI ET AL.
tive target for studies of improved glucose uptake and in-
sulin sensitivity. The current research has shown that one of
the mechanisms of reduced blood glucose levels achieved
by Chlorella intake is an activation of insulin signaling path-
ways resulting from changes in gene expression in the pe-
ripheral blood cells. This research also suggests, however,
that changes in gene expression profile in the peripheral
blood can be useful as a surrogate marker when investigat-
ing glucose metabolism. This marker is particularly effec-
tive in research targeting human beings.
The current research also showed that Chlorella intake in
humans is useful in improving fat metabolism. Particularly
in the case of the D Group, significant decreases in total
blood serum cholesterol, HDL-cholesterol, and LDL-cho-
lesterol were observed at all measurement points after the
start of Chlorella intake.
Merchant and Andre
12
used a double blind test to study
the effects of Chlorella intake on symptom improvements
in a total of 55 patients suffering from fibromyalgia syn-
drome, hypertension, and ulcerative colitis. They confirmed
that Chlorella intake lowers cholesterol in the blood, which
is consistent with the outcome of the current research
Shibata et al.
13
reported that in rats raised on feed con-
taining cholesterol, the administration of Chlorella de-
creases cholesterol concentrations in the blood and liver, but
that there were no changes in neutral fat or phospholipid
volumes and that excretion of neutral steroids was increased.
They surmised that the cholesterol-lowering effects of
Chlorella are brought about by increasing neutral steroid
elimination in feces. Sano et al.
14
also reported that in rats
with hyperlipemia created through excess administration of
cholesterol, the administration of Chlorella increased steroid
elimination in the feces. Connor et al.
15
reported that ad-
ministering high-molecular-weight unsaturated fatty acids to
humans increases the neutral steroid content of feces and
also reduces blood cholesterol concentrations. Based on the
fact that about 74% of the fatty acids contained in Chlorella
are unsaturated fatty acids, we can infer that the presence of
a physiological mechanism in which Chlorella intake causes
the reductions in blood cholesterol as follows: Chlorella in-
take may increase neutral steroid elimination in the feces,
causing a concomitant demand for cholesterol in the liver,
which in turn reduces cholesterol concentrations in the
blood.
T
ABLE
3. L
IST OF
G
ENES
T
HAT
S
HOWED
S
IGNIFICANT
D
IFFERENCES IN
E
XPRESSION
L
EVEL
B
ETWEEN THE
D G
ROUP AND THE
N G
ROUP
B
EFORE
THE
S
TART OF THE
C
HLORELLA
I
NTAKE
T
ESTS AND
T
HAT
A
LSO
V
ARIED AS A
R
ESULT OF
C
HLORELLA
I
NTAKE
Target
accession Gene
number symbol Gene name Category
NM_001116.1 ADCY9 Adenylate cyclase 9 Signal
NM_033375.3 MYO1C Myosin IC
NM_000805.2 GAST Gastrin Receptor
NM_021187.1 CYP4F11 Cytochrome P450, family 4, subfamily F, P450
polypeptide 11
NM_022444.3 SLC13A1 Solute carrier family 13 (sodium/sulfate Transporter
symporters), member 1
NM_004718.2 COX7A2L Cytochrome coxidase subunit VIIa polypeptide Metabolism
2-like
U32519.1 Ras-GTPase-activating protein SH3-domain- Signal
binding protein
NM_014585.3 SLC40A1 Solute carrier family 40 (iron-regulated Transporter
transporter), member 1
M96995.1 GRB2 Growth factor receptor-bound protein 2 Signal
NM_001114.1 ADCY7 Adenylate cyclase 7 Signal
U48251.1 PRKCBP1 Protein kinase C binding protein 1 Signal
U21858.1 TAF9 TAF9 RNA polymerase II, TATA box binding Repair
protein-associated factor, 32 kDa
U50062.1 RIPK1 Receptor (tumor necrosis factor receptor Apoptosis
superfamily)-interacting serine-threonine
kinase 1
M92287.1 CCND3 Cyclin D3 Cell cycle
NM_014235.2 UBL4 Ubiquitin-like 4
AF038950.1 ABCB7 ATP-binding cassette, subfamily B (MDR/TAP), Transporter
member 7
NM_002827.2 PTPN1 Protein tyrosine phosphatase, non-receptor Signal
type 1
L25610.1 CDKN1A Cyclin-dependent kinase inhibitor 1A Cell cycle
(p21, Cip1)
In recent years, the so-called Randle hypothesis
16
was
proposed to describe the inhibition of glucose uptake by
abnormalities in fat metabolism, stating that increases
in fatty acids limit the oxidation and uptake of glucose.
This hypothesis has been explained through extensive
experimental results. Another approach has also been
proposed in skeletal muscle cells whereby the uptake of
free fatty acids is stimulated, deactivating the insulin
signal transduction systems that transduce signals from
insulin receptors to GLUT4.
17
In the current research as
well, we can assume that Chlorella intake first improves
fat metabolism, resulting in improved glucose uptake. Al-
though cholesterol levels in the blood decrease, triglyc-
eride concentrations do not necessarily drop, so the
relationship between the improvement of fat metabolism
and the decrease in blood glucose level is unclear at pre-
sent. It will be necessary to conduct further studies,
including in vitro experiments, to elucidate the mecha-
nisms involved.
CONCLUSIONS
In order to clarify the physiological effects of Chlorella
intake on subjects with high-risk factors for lifestyle-related
diseases, we conducted blood biochemical tests on a high-
risk factor group and a healthy subject group and analyzed
gene expression profiles in peripheral blood cells before and
after Chlorella intake. The results of these tests showed that
Chlorella intake brings about improvements in both fat me-
tabolism and glucose metabolism. The expression of genes
involved in the insulin signaling pathway was also affected
by Chlorella intake, especially those related to glucose up-
take in tissue, providing support for the observation that
Chlorella lower blood glucose levels. These results indicate
that changes in gene expression in the peripheral blood can
be useful as a surrogate marker for investigating the mech-
anisms of modulation of glucose sensitivity in humans. In
the clarification of how functional and health foods can con-
tribute to human health, the combination of the nutrige-
NUTRIGENOMICS OF EFFECTS OF CHLORELLA 403
FIG. 2. Schematic diagram of the insulin signaling pathway based on the KEGG database (see text). The changes of expression level of genes
associated with this pathway resulting from Chlorella intake at 4 weeks, 12 weeks, and 16 weeks compared to 0 week value are mapped in the
heat map format; red and green mean up-regulation and down-regulation, respectively. At each gene six boxes are drawn; the three boxes on the
left display change of expression level measured at 4 weeks, 12 weeks, and 16 weeks (from left to right) in the N Group, and the other three
boxes on the right display the data in the D Group. INS, insulin; INSR, insulin receptor; IRS, insulin receptor substrate 1; PI3K, phosphoinosi-
tide-3-kinase; PTB1B, protein tyrosine phosphatase 1B; Akt, v-akt murine thymoma viral oncogene homolog 3; GYS, glycogen synthase 1; FBP,
fructose-1,6-bisphosphatase 1; SHC, Src homology 2 domain containing transforming protein 2; GRB2, growth factor receptor-bound protein 2;
SOS, son of sevenless homolog 1; Ras, v-Ha-ras Harvey rat sarcoma viral oncogene homolog; Raf, v-raf murine sarcoma 3611 viral oncogene
homolog; Elk1, member of ETS oncogene family. Refer to the following URL for further explanations of other abbreviations:
http://www.genome.ad.jp/dbget-bin/www_bget?pathwayhsa04910.
nomics research methods with conventional blood bio-
chemical tests such as those used in this study is being used
more widely.
AUTHOR DISCLOSURE STATEMENT
No competing financial interests exist.
REFERENCES
1. Tanaka K, Konishi F, Himeno K, Taniguchi K, Nomoto K: Aug-
mentation of anti-tumor resistance by a strain of unicellular green
algae, Chlorella vulgaris. Cancer Immunol Immunother 1984;17:
90–94.
2. Ishibashi H: Effects on Chlorella feeding on rats. Biol Abstr
1972;54:9694.
3. Tanaka K, Yamada A, Nada K, Shoyama Y, Kubo C, Nomoto K:
Oral administration of an unicellar green algae, Chlorella vulgaris,
prevents stress-induced ulcer. Planta Med 1997;63:465–466.
4. Woolf SH: Weighing the evidence to formulate dietary guidelines.
J Am Coll Nutr 2006;25(Suppl):277S–284S.
5. Afman L, Muller M: Nutrigenomics: from molecular nutrition to
prevention of disease. J Am Diet Assoc 2006;106:569–576.
6. Benjamini Y, Hochberg Y: Controlling the false discovery rate:
a practical and powerful approach to multiple testing. J R Stat Soc
Ser B 1995;57:289–300.
7. Cheng FC, Lin A, Feng JJ, Mizoguchi T, Takekoshi H, Kubota
H, Kato Y, Naoki Y: Effects of Chlorella on activities of protein
tyrosine phosphatases, matrix metalloproteinase, caspases, cy-
tokine release, B and T cell proliferations, and phorbol ester re-
ceptor binding. J Med Food 2004;7:146–152.
8. Cherng J-Y, Shih M-F: Improving glycogenesis in streptozocin
(STZ) diabetic mice after administration of green algae Chlorella.
Life Sci 2006;78:1181–1186.
9. Cheng J-Y, Shih M-F: Potential hypoglycemic effects of Chlorella
in streptozotocin-induced diabetic mice. Life Sci 2005;77:
980–990.
10. Dimitriadis G, Maratou E, Boutati E, Psarra K, Papasteriades C,
Raptis SA: Evaluation of glucose transport and its regulation by
insulin in human monocytes using flow cytometry. Cytometry A
2005;64:27–33.
11. Estrada DE, Elliot E, Zinman B, Poon I, Liu Z, Klip A, Daneman
D: Regulation of glucose transport and expression of GLUT3
transporters in human circulating mononuclear cells: studies in
cells from insulin-dependent diabetic and nondiabetic individu-
als. Metabolism 1994;43:591–598.
12. Merchant RE, Andre CA: A review of recent clinical trials of the
nutritional supplement Chlorella pyrenoidosa in the treatment of
fibromyalgia, hypertension, and ulcerative colitis. Altern Ther
Health Med 2001;7:79–91.
13. Shibata S, Oda K, Onodera-Masuoka N, Matsubara S, Kikuchi-
Hayakawa H, Ishikawa F, Iwabuchi A, Sansawa H: Hypocho-
lesterolemic effect of indigestible fraction of Chlorella regularis
in cholesterol-fed rats. J Nutr Sci Vitamin (Tokyo) 2001;47:
327–377.
14. Sano T, Kumamoto Y, Kamiya N, Okuda M, Tanaka Y: Effect
of lipophilic extract of Chlorella vulgaris on alimentary hyper-
lipidemia in cholesterol-fed rats. Artery 1988;15:217–224.
15. Connor WE, Witiak DT, Stone DB, Armstrong ML: Cholesterol
balance and fecal neutral steroid and bile acid excretion in nor-
mal men fed dietary fats of different fatty acid composition. J Clin
Invest 1969;48:1363–1375.
16. Randle PJ, Garland PB, Hales CN, Newsholme EA: The
glucose fatty-acid cycle. Its role in insulin sensitivity and
the metabolic disturbances of diabetes mellitus. Lancet 1963;1:
785–789.
17. Roden M: How free fatty acids inhibit glucose utilization in hu-
man skeletal muscle. News Physiol Sci 2004;19:92–96.
404 MIZOGUCHI ET AL.
... Chlorella tablets were administered for 12 months, during breakfast, eight tablets/day (1.6 g) for the first age regimen was determined based on previous clinical trials (Mizoguchi et al., 2008;Panahi et al., 2012;Noguchi et al., 2014;Azocar and Diaz, 2013;Merchant and Andre, 2001;Nakano et al., 2007Nakano et al., , 2010Nagayama et al., 2014;Miyazawa et al., 2013b). ...
... The choice of the doses to be used in the present study was based on clinical studies from the literature. Although improvement with Chlorella ingestion has been observed in different pathologies and the lack of reported side effects is a well-recognized attribute of the alga (Miyazawa, et al., 2013b;Nakano et al., 2007Nakano et al., , 2010Shimada et al., 2009;Lee et al., 2012;Otsuki et al., 2012;Kwak et al., 2012;Otsuki et al., 2011;Nagayama et al., 2014;Merchant et al., 2000;Lee et al., 2010;Mizoguchi et al., 2008;Noguchi et al., 2014;Azocar and Diaz, 2013), no consensus has been reached on the choice of the low effective clinical doses to be used. In this context, studies showed that in patients with nonalcoholic hepatic steatosis, a dose of 1.2 g/day for 3 months, complementary to conventional treatment, produces significant improvements in serum transaminase levels and triglycerides as well as increased sensitivity to insulin (Panahi et al., 2012). ...
... In another study, the administration of 7 g/day for 30 days to women with breast cancer who received radiotherapy and/or chemotherapy for at least 6 months increased QoL in 50% of these women (Noguchi et al., 2014). In a study conducted in healthy volunteers and in people with a high-risk factor for the development of lifestyle-related diseases, the intake of 8 g/day for 12 weeks produced an improvement in fat and glucose metabolism in addition to increased gene expression of factors essential for ideal glycaemic maintenance, such as Akt and IRS (Mizoguchi et al., 2008). In healthy volunteers, 8 g/day for a period of 2 months increased the antioxidant activity in erythrocytes by increasing the plasma and erythrocyte concentrations of lutein and decreasing oxidative injury by reducing the phospholipid hydroperoxide concentration in the erythrocyte membrane (Lee et al., 2010). ...
Article
The long-term effects of Chlorella doses on the inflammatory status and quality of life (QoL) of individuals with type-2 diabetes (T2D), and prediabetes (pre-T2D), and of nondiabetic controls were investigated. Chlorella was administered for 12 months; 1.6 g/day for the first six months and 3 g/day for the following six months. The inflammatory profile was studied by quantification of cytokines, adipokines and incretins. QoL was evaluated using the Short Form-36 health survey questionnaire (SF-36). Evaluations were performed at baseline, 6 (T6) and 12 (T12) months after initiating Chlorella intake. At baseline, QoL was more deeply impacted in T2D, a similar proinflammatory profile was observed in T2D and pre-T2D. In both, at T6 and T12, Chlorella modulated the altered levels of adipocytokines and incretins towards healthy values, and significantly improved QoL. Moderate correlations between the modulation by the alga and enhancement in QoL were observed only in the T2D group. In the nondiabetic control group, Chlorella improved QoL vitality and mental health scores. No differences were found between the two doses. Our results illustrate Chlorella adaptogen activity on inflammatory pathways and suggest its promising use as a complementary alternative in treating diseases related to insulin resistance in a wide range of chronic low-grade systemic inflammation-related diseases. Moreover, Chlorella increased QoL in all groups, the ultimate goal of all healthy interventions. Altogether, our findings suggest that one core mechanism involved in the homeostatic response produced by Chlorella is related to its rich content of carotenoids, operating mainly through inhibition of the NF-κB signalling pathway.
... However, neither CV nor HIIT, alone or in combination with each other, led to any significant changes in FFM. In an RCT, as done by Mizoguchi et al., supplemented with CV (40 tablets/d) for 16 weeks, the reducing effect of CV on body fat reduction was attributed to a gene named protein tyrosine phosphatase 1B (PTP-1B), a negative regulator of insulin pathway and leptin (22) . Besides this, the chlorophyll content of CV may decrease the FM via suppressing adipogenesis and activating white adipose tissue browning (23,24) . ...
Article
The beneficial effects of high-intensity interval training (HIIT) and chlorella vulgaris (CV) on body composition and mitochondrial biogenesis have been shown in some mechanistic studies. This study aimed to determine the effects of CV and/or HIIT on mitochondrial biogenesis, performance and body composition among overweight/obese women. There was a significant reduction in the fat mass (FM) of the CV þ HIIT group, as compared with the placebo group (P = 0·005). A marginal significant increase in body water (P = 0·050) and PPAR-γ coactivator-1α (P = 0·050) was also found only in the CV þ HIIT group, as compared with the placebo. Relative (P < 0·001) and absolute (P < 0·001) VO 2max , as well as Bruce MET (P < 0·001), were significantly increased in the HIIT and HIIT þ CV groups. Besides, the synergistic effect of CV and HIIT on the Bruce MET increment was found (interaction P-value = 0·029). No significant changes were observed in BMI, fat-free mass, visceral fat, silent information regulator 1 and fibroblast growth factor-21. In this randomised clinical trial, forty-six overweight/obese women were assigned to four groups including CV þ HIIT and HIIT þ placebo groups that received three capsules of CV (300 mg capsules, three times a day) or corn starch, in combination with three sessions/week of HIIT. CV and placebo groups only received 900 mg of CV or corn starch, daily, for 8 weeks. Biochemical assessments, performance assessment and body composition were obtained at the beginning and end of the intervention. HIIT may be, therefore, effective in improving mitochondrial biogenesis, performance and body composition in overweight/obese women. Total body fat is associated with impaired mitochondrial function , thus indicating a strong relationship between body composition and mitochondrial energy metabolism (1). Mitochondria, as an important cell organelle, is involved in many crucial cell functions such as metabolism, regulating the maximal oxygen consumption (VO 2max), which is important for endurance performance (2). VO 2max is the maximum (max) amount of oxygen (O 2) a person utilises during his/her exercise; it is considered as a common measurement of aerobic power. Some characteristics including sex, age, body composition, exercise history and diet can affect VO 2max (3). Endurance exercise-induced adaptations in mitochondrial activity can improve the metabolic health and decrease the risk of obesity and other metabolic disturbances (4). Higher mitochondrial biogenesis is associated with aerobic performance as well as muscle oxidative capacity and regulated by transcriptional cofactors such as PPAR-γ coactivator-1α (PGC-1α) (5). Deacetylation of PGC-1α by silent information regulator 1 (SIRT1) which is an NAD-dependent deacetylase increases PGC-1α activity, resulting in the activation of mitochondrial bio-genesis (6,7). Besides, the gene expression of PGC-1α is up-regulated via fibroblast growth factor-21 (FGF-21) (8) .
... Evaluations were performed at baseline and 30 days after initiating Chlorella intake. The dosage regimen was determined based on previous clinical trials (Azocar and Diaz, 2013;Merchant and Andre, 2001;Miyazawa et al., 2013b;Mizoguchi et al., 2008;Nagayama et al., 2014;Nakano et al., 2007Nakano et al., , 2010Noguchi et al., 2014;Panahi et al., 2012). ...
Article
To investigate the effects of Chlorella alga on gut microbiota dysbiosis in type-2 diabetes (T2D). The stress perception of patients was also investigated. Chlorella (3 g/day) was administered to patients with T2D (n = 10) for a period of 30 days. Gut microbiota composition was analysed by 16S rDNA gene sequencing, and stress perception was evaluated using the perceived stress scale (PSS). A total of 13 phyla, 89 families, and 185 genera were identified from all faecal samples of patients with T2D, and Firmicutes and Bacteroidetes were the most dominant phyla among all samples. Chlorella decreased Bacteroidetes and increased Firmicutes. The proportions of the Akkermansia, Coprococcus, Dorea, Lachnospira, Phascolarctobacterium, and Ruminococcus generas increased, whereas the proportion of Paraprevotella, Prevotella, Klebsiella, and Sutterella decreased in the faeces of patients with T2D after Chlorella intake. Chlorella induced a significant reduction in perceived stress in patients with T2D, and better PSS scores negatively correlated with an increase in Akkermansia, Coprococcus, Dorea, Lachnospira, Phascolarctobacterium, and Ruminococcus and positively correlated with a decrease in Paraprevotella, Prevotella, Klebsiella, and Sutterella. Altogether, these results show the ability of Chlorella to positively modulate gut dysbiosis, leading to reduced stress perception in patients with T2D. Our findings contribute to the globally increasing search for new preventive and therapeutic strategies aimed at restoring the balance of the intestinal ecosystem.
... The algal extract possesses many effective chemical compounds that have the ability to dissolve in water, such as saponins, glycosides, carbohydrates and phenols. These compounds have a significant effect in reducing the level of glucose in the blood, especially in animals with hyperglycemia, because these compounds possess the ability to stimulate the body tissues to uptake glucose from the blood, so the tissue's consumption of glucose increases [26]. ...
Article
Full-text available
The present study was designed to study the efficacy of Spirulina platensis algal extract on hepatocellular carcinoma cell lines (HAMC Cell line), as well as its antidiabetic effect on alloxan-induced diabetic male rabbits. The study included the treatment of 24 male rabbits for four periods (7, 14, 21, 28) of days. The experiment included four groups of rabbits: the negative group, the positive group, the first treatment group and the second treatment group. Each group contained six rabbits. The negative (intact) and positive (diabetic induced), control groups were injected with 1ml of the normal saline and the first treatment group (diabetic induced) was injected with a concentration of 50 mg/kg of the algal extract. In contrast, the second treatment group (diabetic induced) was injected with a concentration of 100 mg/kg of the algal extract. The treatment results with algal extract showed a significant decrease in blood glucose levels in the first and second treatment groups at a level of probability (P<0.05) compared with the positive control group for all periods. The results also showed that the algal extract had efficacy against cancer, as the concentration of 17.2 µg caused the highest HAMC cell line inhibition rate at 62.23%. The current study concluded that Spirulina platensis had therapeutic effects in alloxan-induced diabetic rabbits as well as high potential inhibition of cancer cells.
... Chlorella supplementation in humans has been shown to have antioxidant [169], antidiabetic [170], immunomodulatory [171], and antihypertensive properties [172]. Chlorella intake resulted in noticeable reductions in body fat percentage, total blood serum cholesterol, and fasting blood glucose levels [173]. Chlorelladerived multicomponent supplementation decreases arterial stiffness in young people [174] and middle-aged and senior adults [175]. ...
Article
Full-text available
Microalgae are photosynthetic cyanobacteria and eukaryotic microorganisms, mainly living in the water. In agriculture, numerous studies have been conducted to utilize microalgae as a biostimulant resource. Scenedesmus has been known to be one such microalga that can promote plant growth by secretion of auxin or cytokinin hormone analogs. However, no research has been performed on the effect of microalgae treatment on plant microbiota communities. This study was conducted to investigate the mode of action of microalgae as biostimulants in a plant microbiota perspective by using Scenedesmus sp. CHK0059 (also known as species Chlorella fusca), which has been well documented as a biostimulant for strawberries. The strawberry cultivar Keumsil was bred with Seolhyang and Maehyang as the parent cultivars. Using these three cultivars, microbiota communities were evaluated for changes in structural composition according to the CHK0059 treatment. CHK0059-treated Seolhyang, and CHK0059-untreated Maehyang were similar in microbial diversity in the endosphere. From a microbiota community perspective, the diversity change showed that CHK0059 was affected by the characteristics of the host. Conversely, when CHK0059 treatment was applied, populations of Streptomyces and Actinospica were observed in the crown endosphere.
... Chlorella tablets are quite effective in treating cardiovascular diseases. "Sun Chlorella A ′′ tablets (Sun Chlorella Corp., Kyoto, Japan), which contains more than 95.5% dried Chlorella powder were proved that can improve fat and glucose metabolism and affect the expression of genes involved in the insulin signaling pathway, resulting in low blood glucose levels (Toru et al., 2008). Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder. ...
Article
Microalgae is an autotrophic organism with fast growth, short reproduction cycle, and strong environmental adaptability. In recent years, microalgae and the bioactive ingredients extracted from microalgae are regarded as potential substitutes for raw materials in the pharmaceutical and the cosmetics industry. In this review, the characteristics and efficacy of the high-value components of microalgae are discussed in detail, along with the sources and extraction technologies of algae used to obtain high-value ingredients are reviewed. Moreover, it also includes the latest trends in biotherapy based on high-value algae extracts as materials. In addition, the excellent antioxidant properties of microalgae derivatives are regarded as potential substitutes for safe and environmentally friendly cosmetic production. Only by further studying the mechanism of microalgae bioactive compounds and conducting reasonable clinical trials can safe and compliant microalgae-derived drugs or cosmetics be marketed.
... Lee et al.'s study showed that C. vulgaris increases the excretion of stool and lipids and thereby leads to a reduction in the total serum lipids and also decreases the triglycerides (TG) and total cholesterol (TC) in the liver (Lee et al., 2008). Another study revealed that administration of chlorella tablets for 16 weeks resulted in activation of insulin signaling pathways that subsequently led to a decrease in fasting blood sugar (FBS) and TC (Mizoguchi et al., 2008). ...
Article
Full-text available
This study was aimed to investigate the effect of microalgae Chlorella vulgaris (C. vulgaris) on nonalcoholic fatty liver disease (NAFLD)-related complications induced by high-fat diet (HFD). Fifty adult male rats were divided into six groups. Control group and HFD group treated with or without C. vulgaris 5% and 10%. Biochemical parameters in serum were measured by spectrophotometric and enzyme-linked immunosorbent assay (ELISA) methods. The relative gene expression levels of Tumor Necrosis Factor-alpha (TNF-α), NF-kappa B (NF-ƙB), and p38 Mitogen-Activated Protein Kinases (p38 MAPK) in the liver were assessed by using quantitative real-time PCR, while the protein levels of NF-ƙB and TNF-α in the liver homogenate were determined by ELISA. The effects of HFD significantly were reversed by C. vulgaris, especially at a 10% dose. Therefore, it can be concluded that C. vulgaris therapeutically could be useful to improve NAFLD and its complications. Practical applications It is established that NAFLD is associated with the resistance to insulin, dyslipidemia, and inflammation. Accordingly, modulating of these conditions may be useful in the management of NAFLD. Our results showed the effectiveness of C. vulgaris against NAFLD-related complication through the alleviating insulin resistance, dyslipidemia and also down-regulation of inflammatory genes in p38 MAPK/TNF-α/NF-ƙB pathway. The results of our study may be useful for scientist to prepare an effective supplement from C. vulgaris to overcoming NAFLD-related complications.
Chapter
In the new era of scientific research, the word ‘Omics’ has been the most significant term. This term comes up with the ideology of studying and analyzing almost all the aspects of biological systems, which specifically concentrate on a complex system of life. It also includes high‐throughput molecular biology techniques used by computational drug discovery tools. The use of this technology is mainly to study, analyze and interpret the data of the entire human genomic sequence, which is the most significant achievement in the discipline of biomedical and bio‐informational scientific research. Comprehensive data analysis is accomplished using a multidisciplinary approach such as microarrays and other bioinformatics tools, so it becomes easier for researchers to examine the biological activity of 30,000 human genes and polymorphism on large scale beyond 20 lakhs numbers. Polymorphism is relatively common, known for its dynamic functions and interaction, which affects the human species, nowadays it is considered rare, but the vast majority of them are single nucleotide polymorphisms. As “Omics” techniques are used to expose the network among gene products, as humans are genetically similar, they could aid greatly in disease diagnosis and treatment by monitoring and analyzing the interaction of biomolecules in living systems.
Article
Heavy reliance on fossil fuels has been associated with increased climate disasters. As an alternative, microalgae have been proposed as an effective agent for biomass production. Several advantages of microalgae include faster growth, usage of non-arable land, recovery of nutrients from wastewater, efficient CO2 capture, and high amount of biomolecules that are valuable for humans. Microalgae Chlorella spp. are a large group of eukaryotic, photosynthetic, unicellular microorganisms with high adaptability to environmental variations. Over the past decades, Chlorella has been used for the large-scale production of biomass. In addition, Chlorella has been actively used in various food industries for improving human health because of its antioxidant, antidiabetic, and immunomodulatory functions. However, the major restrictions in microalgal biofuel technology are the cost-consuming cultivation, processing, and lipid extraction processes. Therefore, various trials have been performed to enhance the biomass productivity and the lipid contents of Chlorella cells. This study provides a comprehensive review of lipid enhancement strategies mainly published in the last five years and aimed at regulating carbon sources, nutrients, stresses, and expression of exogenous genes to improve biomass production and lipid synthesis.
Article
Background The beneficial effects of high intensity interval training (HIIT) and chlorella vulgaris (CV) on body composition and mitochondrial biogenesis have been shown in some mechanistic studies. This study aimed to determine the effects of CV and/or HIIT on mitochondrial biogenesis, performance and body composition among overweight/obese women. Methods In this randomized clinical trial, 46 overweight/obese women were assigned to four groups including CV+HIIT and HIIT+placebo groups that received three capsules of CV (300 mg capsules, 3 times a day) or corn starch, in combination with three sessions/week of HIIT. CV and placebo groups only received 900mg of CV or corn starch, daily, for 8 weeks. Biochemical assessments, performance assessment and body composition were obtained at the beginning and end of the intervention. Results There was a significant reduction in the fat mass of the CV+HIIT group, as compared with the placebo group (p=0.005). A marginal significant increase in body water (p=0.050) and peroxisome proliferator-activated receptor-γ coactivator 1 ɑ (p=0.050) was also found only in the CV+HIIT group, as compared with the placebo. Relative (p<0.001) and absolute (p<0.001) VO2max, as well as Bruce MET (p<0.001), was significantly increased in the HIIT and HIIT+CV groups. Besides, the synergistic effect of CV and HIIT on the Bruce MET increment was found (interaction p-value =0.029). No significant changes were, observed in BMI, fat free mass, visceral fat, silent information regulator 1 and fibroblast growth factor-21. Conclusions HIIT may be, therefore, effective in improving mitochondrial biogenesis, performance and body composition in overweight/obese women.
Article
Full-text available
The common approach to the multiplicity problem calls for controlling the familywise error rate (FWER). This approach, though, has faults, and we point out a few. A different approach to problems of multiple significance testing is presented. It calls for controlling the expected proportion of falsely rejected hypotheses – the false discovery rate. This error rate is equivalent to the FWER when all hypotheses are true but is smaller otherwise. Therefore, in problems where the control of the false discovery rate rather than that of the FWER is desired, there is potential for a gain in power. A simple sequential Bonferroni-type procedure is proved to control the false discovery rate for independent test statistics, and a simulation study shows that the gain in power is substantial. The use of the new procedure and the appropriateness of the criterion are illustrated with examples.
Article
The effect of glycolipid (GL) and phospholipid (PL) fractions obtained from Chlorella on serum lipid level and fecal excretion of steroids were examined in cholesterol-fed rats. The increase of the level of serum lipids were inhibited by the feeding of GL, PL and Chlorella powder almost the same degree. Fecal excretion of steroids (mostly of cholesterol, deoxycholic and lithocholic acid) were increased by feeding of GL and PL fractions. It is concluded that the feeding of each fraction inhibits the absorption of exogenous steroids and promotes turnover of bile acids in liver to suppress the increase of serum cholesterol level caused by administration of high cholesterol diet.
Article
Six normal men were fed formula diets containing either highly saturated fat (cocoa butter, iodine value 32) or polyunsaturated fat (corn oil, iodine value 125). The sterol balance technique was used to compare the changes in serum cholesterol concentration with the excretion of fecal steroids. The method used for the analysis of fecal steroids was chemical, with a final identification and quantification by gas-liquid chromatography. It was confirmed that the chemical method for fecal steroid analysis was accurate and reproducible. The three dietary periods were each 3 wk in length. In sequence, cocoa butter (period I), corn oil, and cocoa butter (period III) were fed at 40% of the total calories. All diets were cholesterol free, contained similar amounts of plant sterols, and were identical in other nutrients. Corn oil had a hypocholesterolemic effect. Mean serum cholesterol concentrations were 222 mg/100 ml (cocoa butter, period I), 177 during corn oil, and 225 after the return to cocoa butter. Individual fecal steroids were determined from stools pooled for 7 days. Both neutral steroids and bile acids were altered significantly by dietary polyunsaturated fat. The change in bile acid excretion was considerably greater than the change in neutral steroids. Corn oil caused a greater fecal excretion of both deoxycholic and lithocholic acids. The total mean excretion (milligrams per day) of fecal steroids was 709 for cocoa butter (period I), 915 for corn oil, and 629 for the second cocoa butter period. The enhanced total fecal steroid excretion by the polyunsaturated fat of corn oil created a negative cholesterol balance vis-à-vis the saturated fat of cocoa butter. The hypocholesterolemic effect of polyunsaturated fat was associated with total fecal sterol excretion twice greater than the amount of cholesterol calculated to leave the plasma. This finding suggested possible loss of cholesterol from the tissues as well.
Article
Growth of Meth-A tumor in CDF1 mice was inhibited significantly by injection of a hot water extract of a strain of Chlorella vulgaris (CE) into the tumor or into the subcutaneous tissue near the tumor. The augmentation of resistance by CE may require the participation of T cells and macrophages, since it was abolished or reduced in athymic nude mice or mice treated with carrageenan, a macrophage blocker. Mice treated with CE exhibited antigen-specific augmented resistance against rechallenge with tumor. Moreover, the antitumor effect of CE was comparable with that of Corynebacterium parvum, but its mechanism of effect might be different.
Article
We have previously shown that human circulating mononuclear cells (CMCs) respond to physiological concentrations of insulin with a rapid increase in glucose transport rate. The responding cells were found to be the monocytes, and cells derived from individuals with insulin-dependent diabetes mellitus (IDDM) had lower basal and insulin-stimulated glucose transport rates. Of interest, both cell types were found to express the GLUT1 but not the typical insulin-responsive GLUT4 transporter isoform. To further study the mechanisms responsible for stimulation of transport in these cells, we investigated (1) the response to insulin-like growth factor-I (IGF-I) and insulin-mimetic agents, and (2) the expression of other glucose transporter isoforms in CMCs of nondiabetic and IDDM individuals. The time course of insulin-stimulated glucose uptake in CMCs was rapid, reaching a plateau within 30 minutes. CMCs showed a dose-dependent and highly sensitive increase in glucose uptake to IGF-I (maximal response reached at 0.1 to 0.5 nmol/L IGF-I). The IGF-I dose-response curve was similar for CMCs of control and IDDM individuals, but both the basal and maximal response to IGF-I were lower in the diabetic group (P < .01). CMCs did not respond to vanadate, lithium, hydrogen peroxide, or short incubation (1 hour) with metformin, but glucose uptake increased in response to peroxides of vanadate and longer-duration (14 hours) metformin incubations. The glucose transporter isoforms of separated monocytes and lymphocytes were further investigated by Northern blotting of total RNA with a GLUT3-specific cDNA probe and by Western blotting of total membranes using GLUT3-specific antiserum.(ABSTRACT TRUNCATED AT 250 WORDS)
Article
Oral administration of dry powder of Chlorella vulgaris (CVP) showed clear prophylactic effects in water-immersion restraint stress-induced and in cysteamine-induced peptic ulcer models, but not in Shay's rat model. Drugs that enhance the protective factors of ulcer formation are effective in the first two models. CVP may prevent ulcer formation mainly through the "immune-brain-gut" axis and protection of gastric mucosa by its own characteristics.
It has been suggested that the consumption of natural "whole foods" rich in macronutrients has many healthful benefits for those who otherwise ingest a normal, nonvegetarian diet. One example is dietary supplements derived from Chlorella pyrenoidosa, a unicellular fresh water green alga rich in proteins, vitamins, and minerals. To find evidence of the potential of chlorella dietary supplements to relieve signs and symptoms, improve quality of life, and normalize body functions in people with chronic illnesses, specifically fibromyalgia, hypertension, and ulcerative colitis. Double-blind, placebo-controlled, randomized clinical trials. Virginia Commonwealth University's Medical College of Virginia. Fifty-five subjects with fibromyalgia, 33 with hypertension, and 9 with ulcerative colitis. Subjects consumed 10 g of pure chlorella in tablet form and 100 mL of a liquid containing an extract of chlorella each day for 2 or 3 months. For fibromyalgia patients, assessments of pain and overall quality of life. For hypertensive patients, measurements of sitting diastolic blood pressure and serum lipid levels. For patients with ulcerative colitis, determination of state of disease using the Disease Activity Index. Daily dietary supplementation with chlorella may reduce high blood pressure, lower serum cholesterol levels, accelerate wound healing, and enhance immune functions. The potential of chlorella to relieve symptoms, improve quality of life, and normalize body functions in patients with fibromyalgia, hypertension, or ulcerative colitis suggests that larger, more comprehensive clinical trials of chlorella are warranted.
Article
The effects of Chlorella regularis powder (CP) and Chlorella regularis indigestible fraction (CIF) on serum and liver lipid concentrations and on fecal steroid excretion were estimated in rats fed diets containing 5 g/kg cholesterol and 2.5 g/kg sodium cholate. The ingestion of 12.7% CP or 5.3% CIF did not influence food intake or growth. CP and CIF decreased the levels of serum cholesterol, but had no effect on the levels of serum triacylglycerol and phospholipid. Liver cholesterol contents were lower in the CP and CIF groups than in the control group, but CP and CIF did not affect liver triacylglycerol content. CP and CIF increased the total amount of fecal neutral steroids excreted, but did not modify the total bile acid excretion. However, the soluble bile acid concentrations of reconstituted fecal water in the rats fed CP and CIF diets were lower than the control value. Moreover, CP and CIF had a high bile acid binding capacity in vitro. These results indicated that CIF had a hypocholesterolemic effect and enhanced fecal neutral steroid excretion while decreasing the soluble fecal bile acid concentration.
Article
Rat muscle studies suggest competition between free fatty acids (FFA) and glucose for oxidation, resulting in glucose-6-phosphate accumulation. However, FFA decrease glucose-6-phosphate in human skeletal muscle, indicating direct inhibition of glucose transport/phosphorylation. This mechanism could redirect glucose from muscle to brain during fasting and explain the insulin resistance associated with high-lipid diets and obesity.