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Article
Hepatoprotective effect of Omega-3
PUFAs against acute paracetamol-
induced hepatic injury confirmed by
FTIR
Zeinab A El-Gendy
1
, Seham A El-Batran
1
, SAH Youssef
2
,
A Ramadan
2
, Walid El Hotaby
3
, Rofanda M Bakeer
4,5
and Rania F Ahmed
1
Abstract
Acute paracetamol over dose-induced hepatotoxicity is considered an important medical hazard especially
among women. Omega-3 long-chain polyunsaturated fatty acids (Omega-3 PUFAs) daily doses are nowadays
recommended for their antioxidant and anti-inflammatory potentials. Fourier transform infrared (FTIR) spec-
troscopy is considered a reliable method in analyzing cellular alterations and is now efficiently used to diagnose
several diseases and the efficacy of drugs even in the early stages. The aim of our study was to evaluate the
hepatoprotective effect of Omega-3 PUFAs against paracetamol-induced hepatotoxicity in rats confirmed
through measuring protein alterations in hepatocytes by FTIR. Rats were pretreated with Omega-3 PUFAs
(50 and 100 mg/kg) for 21 days prior to oral ingestion of paracetamol. FTIR results revealed that Omega-3
PUFAs (50 mg/kg) limited the toxic effects of paracetamol by restoring the hepatic amide I to amide II ratio. In
addition; biochemical analyses demonstrated that serum ALT, AST, Cholesterol, LDL-cholesterol and Il-6
levels as well as hepatic TNF-a, MDA, NOx levels were decreased. Besides; serum HDL-cholesterol level
and hepatic GSH level were increased. Histopathological examinations of hepatic sections validated the
hepatoprotective potential. The overall effect of this dose was comparable to those of the usual recommended
hepatoprotective supplement; silymarin. In conclusion; it would be recommended to use Omega-3 PUFAs in
low doses on daily bases as a hepatoprotective agent.
Keywords
Omega-3, paracetamol, liver injury, FTIR
Introduction
Paracetamol is a safely and commonly prescribed
analgesic and antipyretic particularly among women;
yet acute overdose could lead to hazardous and life
threatening hepatotoxicity.
1,2
The main reason for
development of such medical complication is the pro-
duction of N-acetyl-p-benzoquinoneimine (NAPQI),
resulting from the oxidation of paracetamol by the
cytochrome P450 enzyme family. In normal condi-
tions this metabolite binds to glutathione but in cases
of overdoses, glutathione stores are depleted and as
a result; NAPQI binds to cellular proteins.
3,4
Over-
production of reactive oxygen species, inflamma-
tory cascade and consequent cell death follows.
1
Department of Pharmacology, Medical Research Division,
National Research Centre, Dokki, Giza, Egypt
2
Department of Pharmacology, Faculty of Veterinary Medicine,
Cairo University, Giza, Egypt
3
Department of Spectroscopy, Physics Division, National
Research Centre, Dokki, Giza, Egypt
4
Department of Pathology, Faculty of Medicine, Helwan Univer-
sity, Helwan, Egypt
5
Department of Pathology, October University of Modern
Sciences and Arts (MSA) University, Egypt
Corresponding author:
Rania F Ahmed, Department of Pharmacology, National Research
Centre, Dokki, 12622, Giza, Egypt.
Emails: dr_rania_fouad@yahoo.com; dr.rania.fouad@gmail.com
Human and Experimental Toxicology
2021, Vol. 40(3) 526–537
ªThe Author(s) 2020
Article reuse guidelines:
sagepub.com/journals-permissions
DOI: 10.1177/0960327120954522
journals.sagepub.com/home/het
Therefore; the availability of glutathione and antiox-
idant moieties could have a marked impact in the
prevention of acute paracetamol-induced hepatic
insult.
5,6
Marine derived Omega-3 long-chain polyunsatu-
rated fatty acids (Omega-3 PUFAs) especially, eico-
sapentaenoic acid (EPA) and docosahexaenoic acid
(DHA) have long been reported for their valuable
hepatoprotective effects and their ability to decrease
hepatic injury and steatosis.
7–9
They have a variety of
proposed mechanisms of action; the most significant
of which would be; modulating cell proliferation, reg-
ulating fatty acid metabolism, inhibiting lipogenesis
as well as suppressing inflammation and oxidative
stress.
10,11
Silymarin is a well-known traditional herbal medi-
cine extracted from Milk thistle (Silybum marianum
L. Gaertn) fruits. Previously it has been reported to
exert hepatoprotection by several mechanisms such
as; scavenging free radicals, raising the glutathione
content, inhibiting lipid peroxidation, generating mem-
brane stabilization and restoring enzymes levels.
12,13
Fourier transform infrared (FTIR) spectroscopy is
considered a reliable method in providing discern-
ments into disease progression at the molecular level
by monitoring the vibration modes of functional groups
present in proteins, lipids, polysaccharides, and nucleic
acids in the tissue. Due to its numerous advantages;
being cheap, accurate and less time consuming than
the traditional pathological measurements that use
stains and immunohistochemical markers; it is becom-
ing an increasingly powerful tool to diagnose several
diseases even in the early stages.
14,15
Therefore; our study aimed to explore the hepato-
protective potential of Omega-3 PUFAs against
paracetamol-induced toxicity in rats. The different
mechanisms by which Omega-3 PUFAs exert their
activity were investigated; specially their effect on liver
protein secondary structural alterations; confirmed by
FTIR technique. Female rats were used to in our study to
evaluate whether it would be useful to use Omega-3
PUFAs as a supplement in women to overcome the
possibility of development of paracetamol-induced
liver injury.
Materials and methods
Animals
Adult Female Wistar albino rats, 200–250 g were
obtained from the animal house colony, National
Research Centre NRC, Giza, Egypt. All animals were
housed in a well-ventilated environment (8/cage,
22 +3C, 55 +5%humidity and 12 h dark & light
cycles); received standard rat food pellets and water
was provided ad libitum throughout the experimental
period. The animals were treated according to the
national and international ethics guidelines stated by
the ethics committee of NRC. The study’s approval
No. is 13/111.
Drugs
Paracetamol (GSK co, EGYPT) provided as powder.
Omega-3 PUFAs (Vitamin World, Inc. Ronkonkoma,
NY11779 U.S.A.) provided as oily solution. Silymarin
(MADAUS GmbH 51101, Koln, Germany) purchased
as tablets every tablet contains 70 mg of silymarin. Due
to poor water solubility and the physical properties of
the treatments; they were carefully daily freshly pre-
pared in distilled water as a suspension prior to admin-
istration with continuous shaking before ingestion to
assure homogenate suspension.
Experimental design
Study groups (eight female rats each) were treated as
follows: Group (1) Control group (untreated group):
Receiving oral distilled water ingestion (5 ml/kg).
Group (2) Paracetamol group: Receiving oral distilled
water ingestion (5 ml/kg). Group (3) Standard group:
Receiving silymarin at dose of 100 ml/kg/day p.o.
16
Group (4): (O-50): Receiving Omega-3 PUFAs at
dose of 50 mg/kg/day p.o. Group (5): (O-100):
Receiving Omega-3 PUFAs at dose of 100 mg/kg/day
p.o.
17
All groups received the corresponding drug
treatments for 21 days. On day 21 all groups except
the first group were administered paracetamol (600
mg/kg p.o.).
18
Twenty-four hours later blood samples
were collected by orbital puncture of the retro-orbital
plexus
19
; under phenobarbital anesthesia using spe-
cial glass capillary tubes. The collected samples were
allowed to clot, then centrifuged for 20 min at 3000
r.p.m. Serum was separated and stored into Eppendorf
tubes at –20C to be used for determination of liver
function parameters including (AST), (ALT), (HDL-
Cholesterol), (LDL-Cholesterol), Total Cholesterol,
(IL-6) and (TNFa). After collection of blood samples,
rats were sacrificed by decapitation and their livers
were immediately removed. Each liver was divided
into three parts; the first part was preserved in saline
and used for FTIR examination. The second part was
kept at 80C for determination of (MDA), (GSH)
and (NOx). The third part was preserved in phosphate
El-Gendy et al. 527
buffered formalin 10%for further histopathological
investigation.
FTIR micro-spectroscopical analysis of biological
tissues
At postmortem, liver was immediately excised from
rats, trimmed of connective tissue and a part of the
liver was immediately placed in liquid nitrogen then
storage in at 80C for FTIR measurements the sam-
ples were freeze dried in lyophilizer then dried pow-
der were analyzed using VERTEX 70 FTIR (Fourier
Transform Infrared Spectrometer) and the IR Spectra
were recorded in a spectral range of 4000–400 cm
1
,
resolution 2 cm
1
and scan speed 2 mm/s with using
ATR unit with Diamond crystal.
20
Determination of liver function parameters
(ALT and AST)
Serum activities of (ALT) and (AST) were deter-
mined spectrophotometrically at wave length 546
nm.
21
Determination of lipid profile parameters (total
cholesterol, high and low densities lipoproteins
Serum total cholesterol, HDL-Cholesterol and LDL-
Cholesterol were measured spectrophotometrically at
wave length 500 nm.
22–24
Determination of inflammatory markers
Determination of serum interleukein-6. This test was per-
formed using Rat Interleukin 6 enzyme-linked immu-
nosorbent assay (ELISA) kit (Glory Science Co.) for
the quantitative determination of rat IL-6 concentra-
tion at wave length 450 nm.
25
Determination of tissue tumor necrosis factor-alpha.
Serum levels of TNF-awere quantified as performed
by enzyme-linked immunosorbent assay (ELISA) kit
(Glory science Co.) and read at 450 nm.
26
Determination of anti-oxidant activity, oxidative
state and nitrosative stress
Reduced glutathione, malondialdehyde and nitric oxide in
liver tissue. Supernatant of rat liver homogenate (20%)
was used for the spectrophotometric determination of
reduced glutathione (GSH) at wave length 405 nm,
27
(MDA) at wave length 534 nm,
28
and nitric oxide (NO
x
)
at wave length 540 nm.
29
Histopathological examination
For histopathological studies, autopsy samples were
taken from the liver of rats from different groups and
fixed in 10%formal saline for 24 h. Washing was done
in tap water then serial dilution of alcohol (methyl,
ethyl and absolute ethyl) were used for dehydration.
Specimens were cleared in xylene and embedded in
paraffin at 56C in hot air oven for 24 h. Paraffin bees
wax tissue blocks were prepared for sectioning at 4
microns thickness by sledge microtome. The obtained
tissue sections were collected on glass slides, deparaf-
finized, stained by hematoxylin and eosin stain for
routine examination then examination was done
through the light electronic microscope.
30
Immunohistochemistry
Demonstration of Bax and activated Caspase-3 immu-
nostaining in liver sections of normal and treated
rats, as apoptotic markers, was performed accord-
ing to the method described by Ibrahim et al.
31
Rat
anti-caspase-3 (diluted to 1:1000, Abcam, Ltd.,
USA) and Bax (1:200, Abcam, Ltd., USA) were
used as biotinylated primary antibodies. Color
intensity of positive immune-reactive cells was
determined in 10 random low microscopic field
(X10) using Image analyzer (Leica Qwin 500,
Cambridge, England). The image was transformed
into a gray image [a grid of pixels each represent-
ing the intensity or brightness at that point by a
range of numbers, typically from 0 (black) to 255
(white)]. A grayscale image is a color mode that
displays image using 256 shades of gray, referred
to as 8-bit grayscale image. Each color was defined
as a value between 0 and 255, where 0 is the dark-
est (black) and 255 is the lightest (white). Cells
that are positively stained showed brown color
while negative staining is indicated by blue color
Ten different fields were randomly selected under
high-power magnification (x100), and calculations
were performed according to a semi-quantitative
method. The average value was considered as the per-
centage value of apoptosis. The Bax and caspase-3
staining was evaluated as follows:
0 points: Absent hepatocytes staining.
1 point: <25%hepatocytes staining.
2 points: 25–49%hepatocytes staining.
3 points: 50–74%hepatocytes staining.
4 points: 75%hepatocytes staining.
528 Human and Experimental Toxicology 40(3)
Statistical analysis
All results were expressed as mean +standard error
of the mean. Data analysis was achieved by one-way
analysis of variance (ANOVA) followed by Tukey’s
multiple comparison test using software program
Graph Pad Prism (version 8.00). Difference was con-
sidered significant at P < 0.05. Pearson’s correlation
study was conducted for FTIR vs. ALT and AST
using the same software program where difference
was considered significant at P < 0.0332.
Results
Result of FTIR
Paracetamol (600 mg/kg) induced significant
decrease in the ratio of amide I to amide II when
compared to the normal control group. Pretreatment
of rats with Omega-3 (50 and 100 mg/kg) resulted in a
significant protein ratio arousal as compared to para-
cetamol group respectively. Results obtained from the
Omega-3 50 group were superior over those of sily-
marin (Figures 1 and 2).
Effect on serum biochemical parameters
Effect on liver functions
Effect on serum ALT and AST. Paracetamol (600 mg/
kg) induced acute significant increase in serum ALT
and AST levels as compared to the normal control
group. Pretreatment of rats with Omega-3 (50 and
100 mg/kg) significantly lowered both ALT and AST
as compared to the paracetamol group and the results
were comparable to those obtained from silymarin
(Figure 3(a) and (b)). It worth mentioning that the
lower dose of Omega-3 showed better outcomes.
Correlation study: FTIR vs. ALT and AST
Comparing the means of groups; correlation analysis
revealed the existence of a negative correlation
between FTIR and serum ALT level only (R
2
¼
0.8755) at P < 0.0332 (Figure 3(c) and (d)).
Effect on serum lipid profile
Effect on serum HDL, LDL and total cholesterol. Parace-
tamol (600 mg/kg) significantly decreased HDL level
and prompted a significant elevation in total choles-
terol and LDL levels. Silymarin ingestion resulted in a
significant decrease in serum total cholesterol and
LDL levels as compared to paracetamol group. Mean-
while; the HDL level was normalized. Only pretreat-
ment of rats with Omega-3 (50 mg/kg) lowered LDL
level as compared to paracetamol group while both
doses lowered the total cholesterol level as compared
to paracetamol group. In addition; both doses normal-
ized HDL level (Figure 4(a) to (c)).
Effect on serum inflammatory markers
Effect on serum (IL-6). Paracetamol (600 mg/ kg) sig-
nificantly elevated serum IL-6 level. Pretreatment of
rats with Omega-3 (50 and 100 mg/kg) displayed anti-
inflammatory activity lowering serum level of IL-6
Normal
Paracetamol
Silymarin
Omega 50
Omega10
0
1.2
1.3
FTIR
Peak ratio 1637/1537
*
*#
*# *#
Figure 1. Effect of oral administration of Omega-3 on
tissue proteins level (ratio between amide I to amide II
waves. *Significant from normal control,
#
significant from
paracetamol (P < 0.05).
4000 3500 3000 2500 2000 1500 1000 500
Abs.
Wave number cm
-1
control
acetaminophen
Sylimarin
50-O
100-O
Figure 2. The representative FTIR spectra of the experi-
ment, amide 1 appeared at 1637 cm
1
and amide II
appeared at 1537 cm
1
.
El-Gendy et al. 529
(Figure 5). The results were comparable to those of
silymarin and it worth mentioning that Omega-3 at
the lower dose level showed better outcomes.
Effect on tissue (TNF-a)
Paracetamol (600 mg/kg) resulted in a significant eleva-
tion in hepatic tissue TNF-alevel. Pretreatment of rats
with Omega-3 at doses of (50 and 100 mg/kg) induced
a significant reduction in the elevated tissue level of
TNF-a(Figure 6). The results were comparable to those
of silymarin and it worth mentioning that Omega-3 at the
lower dose level showed better outcomes.
Effect on tissue anti-oxidant activity, oxidative
state and nitrosative state
Effect on tissue (GSH), (NO
x
) and (MDA). Paracetamol
(600 mg/kg) prompted a significant reduction in
tissue (GSH) level; in addition to a significant eleva-
tion in tissue (MDA) and (NO
x
). Pretreatment of rats
with Omega-3 at doses of (50 and 100 mg/kg) showed
a pronounced anti-oxidant activity represented by the
significant elevation of GSH level compared to the
normal control along with the normalization of NO
x
level at the group ingesting the lower Omega-3 dose
and the results were comparable to those of silymarin.
Meanwhile the MDA level was only affected at the
lower dose level (Figure 7(a) to (c)).
Histopathological examination and
immunohistochemical study
Histopathological examination of hepatic sections in
the paracetamol intoxicated group revealed extensive
inflammatory cells infiltrating the portal tract and
extending in between hepatocytes. Pyknotic nuclei
of some hepatocytes are observed all over the section
ALT
IU/L
Normal
Paracetamol
Silymarin
Omega 50
Omega100
0
50
100
150
200
*
*#
*#
#
AST
IU/L
Normal
Paracetamol
Silymarin
Omega 50
Omega 100
0
20
40
60
80
100
*
*#
*#
*#
1.25 1.26 1.27 1.28 1.29 1.30 1.31
0
50
100
150
200
FTIR
ALT
1.25 1.26 1.27 1.28 1.29 1.30 1.31
0
20
40
60
80
100
FTIR
AST
(a) (b)
(c) (d)
Figure 3. (a, b) Effect of oral administration of Omega-3 on serum ALT and AST. *Significant from normal control,
#
significant from paracetamol (P < 0.05). (c, d) Correlation study: FTIR vs. ALT and AST.
530 Human and Experimental Toxicology 40(3)
which indicates hepatocellular degeneration. Groups
treated with either silymarin or omega 50 mg/kg
showed scattered inflammatory cells in between
hepatic cords and hepatocytes. On the other hand the
group treated with omega 100 mg/kg displayed exten-
sive inflammatory cellular infiltration and degenerated
LDL
mg/dl
Normal
Paracetamol
Silymarin
Omega 50
Omega100
0
10
20
30
40
50
**
##
HDL
mg/dl
Normal
Paracetamol
Silymarin
Omega 50
Omega 100
0
10
20
30
40
*
#*#
#
Cholesterol
mg/dl
Normal
Paracetamol
Silymarin
Omega50
Omega 100
0
50
100
150
200
*
*#
*# *#
(a)
(c)
(b)
Figure 4. (a–c) Effect of oral administration of Omega-3 on serum lipid profile. *Significant from normal control,
#
sig-
nificant from paracetamol (P < 0.05).
Normal
Paracetamol
Silymarin
Omega50
Omega 100
0
50
100
150
IL-6 (ng/l)
*
*#
*#
*#
Figure 5. Effect of oral administration of Omega-3 on
serum IL-6. *Significant from normal control,
#
significant
from paracetamol (P < 0.05).
Normal
Paracetamol
Silymarin
Omega 50
Omega100
0
500
1000
1500
TNF-alpha (pg/g tissue)
*
*#
*#
#
Figure 6. Effect of oral administration of Omega-3 on tis-
sue TNFa. *Significant from normal control,
#
significant
from paracetamol (P < 0.05).
El-Gendy et al. 531
cells all over examined fields. In conclusion hepato-
cytes induced apoptosis associated with the activation
of caspase and Bax, revealed by their positive brown
immunostaining, expresses that ingestion of Omega-3
at dose level of 50 mg/kg was safer than 100 mg/kg on
liver tissue with minimal side effects and the results
were comparable to those of silymarin (Figure 8).
Normal sections revealed negative staining of both
caspase-3 and Bax point of “0” range. Control positive
revealed point “4” range positivity for both stains
according to the used semi quantitative assessment.
32,33
Omega 50 as well as silymarine Bax staining
revealed point “1” range. Omega 100 Bax showed
point “2” scoring level which was higher than sily-
marine but less than control positive.
Omega 50 caspase-3 revealed point “1” range and
was superior over silymarine which showed point
“2” scoring. Omega 100 caspase-3 showed point
“3” scoring.
Discussion
The present study aimed to evaluate the diverse
means by which Omega-3 PUFAs could hinder acute
paracetamol-induced toxicity in female rats; with
special attention to the effect on liver protein sec-
ondary structural alterations; confirmed by FTIR
technique.
Fourier Transform Infrared (FTIR) micro-
spectroscopy is now considered as a trustable tech-
nique for the biochemical analysis of tissues and cellular
materialsproviding quick, accurate and objective infor-
mation and has been applied in many areas of medical
research.
20,34
Analysis of liver tissue protein alterations
MDA
(b)(a)
(c)
nmol/g tissue
Normal
Paracetamol
Silymarin
Omega50
Omega 100
0
10
20
30
40
50 **
#
*#
NOx
umol/g tissue
Normal
Paracetamol
Silymarin
Omega50
Omega 100
0
20
40
60
*
#
*#
*#
GSH
nmol/g tissue
Normal
Paracetamol
Silymarin
Omega50
Omega 100
0
50
100
150
*
*#
*# *#
Figure 7. (a–c) Effect of oral administration of Omega-3 on tissue GSH, NOx and MDA. *Significant from normal control,
#
significant from paracetamol (P < 0.05).
532 Human and Experimental Toxicology 40(3)
by FTIR micro-spectroscopy could be used as a reliable
marker on the holistic biochemistry of liver tissue. Pre-
vious studies revealed that diseased tissues showed a
reduced ratio of amide I to amide II when compared
with normal tissue revealing a change in protein struc-
ture in diseased liver.
35–37
H & E Caspase BAX
Normal Normal
hepatocellular
architecture.
Normal sections
revealed negative
staining of both
caspase-3 and Bax
point of “0” range.
Paracetamol Inflammatory cells
infiltrating the portal
tract and extend in
between hepatocytes.
Pyknotic nuclei of
some hepatocytes are
observed all over the
section which indicates
hepatocellular
degeneration.
Point “4” range
positivity for both
stains.
Silymarin Congested non
dilated central vein.
Scattered
inflammatory cells in
between hepatic
cords.
Caspase-3 showed
point “2” scoring
while Bax staining
revealed point “1”
range
Omega 50 Dilated slightly
congested central
vein
Few scattered
inflammatory cells in
between hepatocytes.
50 caspase-3 and Bax
staining revealed
point “1” range
Omega 100 Dilated congested CV
Extensive
inflammatory cellular
infiltration
Degenerated cells all
over examined fields
Caspase-3 showed
point “3” scoring
while Bax showed
point “2” scoring
level
Figure 8. Histopathological examination and immunohistochemical study.
El-Gendy et al. 533
Acute hepatotoxicity induced by paracetamol rep-
resents a well-known medicinal complication espe-
cially among women.
38–40
Our study revealed that
amide I and amide II peak ratio was significantly
decreased in paracetamol intoxicated group compared
to the normal control. Moreover; ingestion of a para-
cetamol single acute over dose (600 mg/kg) resulted
in a significant increase in serum ALT, AST, LDL
and total cholesterol as well as a significant reduction
in the HDL level. In addition; liver tissue oxidative
stress was significantly increased indicated by the
elevated levels of MDA and NOx and decreased GSH
level. Inflammatory markers represented by serum
IL-6 and tissue TNF-awere significantly increased.
Finally both histopathological and immunohisto-
chemical examinations certified the existence of
paracetamol-induced severe hepatotoxicity.
Former investigators stated that; acute overdose of
paracetamol resulted in massive destruction to hepa-
tocytes, leading to elevation of serum ALT, AST,
total cholesterol and triglycerides levels; in addition
to a generalized hepatic oxidative stress status repre-
sented by accumulation of MDA as well as NOx and
depletion of GSH. In addition; inflammatory response
represented by elevated level of TNF-awas recorded.
Besides; a significant increase in the levels of
apoptosis-related proteins such as Bax and caspase-
3 was observed suggesting a vital role of apoptosis in
paracetamol-induced hepatic insult.
41–47
Previously, it was reported that; dietary fish oil
supplementation rich in Omega-3 fatty acids
(Omega-3 PUFAs) possessed several medicinal ben-
eficial actions; suppressing inflammatory response
and oxidative stress as well as modulating cell prolif-
eration.
10
The mechanisms underlying the hepatopro-
tective effects of Omega-3 PUFAs includes its ability
to increase GSH along with its capability to scavenge
free radicals and consequently inhibit lipid peroxida-
tion.
9,43
Meanwhile; Maksymchuk, 2014, previously
demonstrated that there was more than two-fold
increase in the content of cytochrome P450 2El
(CYP2E1) in the liver of rats receiving omega-3
PUFAs for 4 weeks in the standard daily diet. In
another study; consumption of omega-3 PUFAs led
to a 3-fold (p < 0.05) increase in CYP2E1 content.
Such changes in the enzyme expression did not have
an impact on the level of lipid peroxidation and on the
prooxidant/antioxidant balance in the liver.
48,49
In
addition; it has been previously reported that
Omega-3 PUFAs inhibit the conversion of arachido-
nic acid into the pro-inflammatory eicosanoids
through cyclooxygenase-2 and 5-lipoxygenase path-
ways either via competing with the substrate or via
inhibiting the activity of eicosanoid-generating
enzymes. Moreover; their metabolites including
resolvins and protectins are involved in hindering
inflammation and steatosis for example; “Resolvin
D1, resolvin E1, and protectin D1” inhibit transen-
dothelial migration of neutrophils into sites of inflam-
mation. Resolvin D1 inhibits IL-1beta production.
Protectin D1 attenuates the production of TNF-alpha
and IL-1beta. Besides, Omega-3 fatty acids were pre-
viously reported to activate peroxisome proliferator-
activated receptors alpha, which up regulate several
genes associated with fatty acid and lipid metabolism
that stimulate fatty acid oxidation, decreasing liver
fats and thus reducing hepatic lipogenesis and steato-
sis. Both ALT and AST levels were reported to be
reduced by Omega-3 PUFAs in several models of
hepatic injury. Finally; it was reported that there was
a direct link between docosahexaenoic acid (DHA)
treatment and suppression of apoptosis represented
by a reduction in active caspase-3.
9,17,50–52
Several
doses have been proposed for the daily intake of
Omega-3 fatty acids with some reports highlighting
that in some cases lower doses would result in
favorable outcomes with less side effects.
17,53
In
our research, (50 mg/kg) of Omega-3 fatty acids
(Omega-3 PUFAs) showed pronounced protection
against paracetamol induced liver damage repre-
sented by increased amide I to amide II peak ratio
compared to the paracetamol intoxicated group.
Furthermore; antioxidant as well as anti-inflammatory
actions and improved serum lipid profile along with
declined levels of serum liver enzymes were detected.
Finally histopathological and immunohistochemical
investigations revealed hepatic tissue protection.
Results were generally comparable to those of
silymarin.
Conclusion
Omega-3 fatty acids could be a very useful supple-
ment in the prevention of liver injury especially in
women but only in low doses.
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest
with respect to the research, authorship, and/or publication
of this article.
534 Human and Experimental Toxicology 40(3)
Funding
The author(s) disclosed receipt of financial support for the
research article: This research was conducted as a part of a
master degree funding program granted by the National
Research Centre (NRC) of Egypt.
ORCID iD
Rania F Ahmed https://orcid.org/0000-0002-9018-512X
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