ArticlePDF Available

Effects of Hyperbaric Oxygen on T helper 17/regulatory T Polarization in Antigen and Collagen-induced Arthritis: Hypoxia-inducible Factor-1α as a Target


Abstract and Figures

Objectives: We sought to investigate and prove the effect of hyperbaric oxygen therapy (HBOT) on T helper 17 (Th17)/regulatory T (Treg) cell polarization through changes in the expression of hypoxia-inducible factor-1 alpha (HIF-1α) in rheumatoid arthritis (RA) animal model. Methods: We used antigen and collagen-induced arthritis (ACIA) as a RA animal model. Sixteen male BALB/c models of ACIA mice were divided into two groups, the non-HBOT group as the control group and the HBOT group as the treatment group. Expression of HIF-1α, Th17 anti-cluster differentiation 196 (CD196), and Treg anti-interleukine 2 receptor β-chain cells (IL-2Rβ) in tissue from the left knee joint tissue were determined histologically. Oxidative stress and systemic inflammation were assessed by levels of superoxide dismutase (SOD), interleukin 17a (IL-17a), C-reactive protein (CRP), and rheumatoid factor (RF) using the enzyme-linked immune-sorbent assay. The degree of arthritis was assessed by clinical scoring of paw swelling and the diameter of paw swelling. Results: We found a significant decrease (p < 0.050) in the expression of HIF-1α, Th17 (CD196), IL-17a, RF levels, and the clinical scores and the diameter of paw swelling when comparing both groups. There was no significant decrease in the level of CRP in the treatment group compared to the control group. The expression of Treg (IL-2Rβ) increased significantly (p < 0.050) and the level of SOD increased but not significantly (p > 0.050) in the treatment group compared to the control group. Conclusions: HBOT has effects on the polarization of Th17 to Treg through a decrease in expression of HIF-1α in mice with ACIA. HBOT is recommended for use as a support therapy for RA in combination with drug therapy.
Content may be subject to copyright.
*Corresponding author:
Rheumatoid arthritis (RA) is a chronic
systemic musculoskeletal disease in
which various joints in the body are
inflamed, leading to swelling, pain,
stiness, and a possible loss of function.1,2 RA is
caused by an imbalance in the number or function
of T helper 17 (Th17) cells and regulatory T
(Treg) cells.3,4 Increased oxidative stress also
participates in the pathogenesis and severity of
the disease.5,6
Oxidative stress in RA can be caused by
deteriorating oxygen supply to the joint tissues
thereby supporting increased reactive oxygen species
(ROS), causing oxidative damage that further
promotes inflammation. Hence, oxidative stress
and inammation are inseparably connected.7,8
Hypoxia-inducible factor-1 alpha (HIF-1α) is a
key transcriptional regulator that enables cellular
metabolic adaptation to low levels of oxygen.9 As
a transcription factor, it inuences and regulates
the expression of dozens of genes involved in
maintaining homeostasis such as changes in oxygen
concentration (oxygen-dependent) and independent
signals.10,11 Superoxide dismutase (SOD) antioxidant
is a protein that functions as important defense
mechanisms for oxidative stress and acts as a rst-
original article O M J [2020], V. 35, N. 1: e90
Eects of Hyperbaric Oxygen on T helper
17/regulatory T Polarization in Antigen
and Collagen-induced Arthritis: Hypoxia-
inducible Factor-1α as a Target
Titut Harnanik
1,2,3*, Joewono Soeroso3, Mohammad Guritno Suryokusumo4
and Tedy Juliandhy5
1Department of Hyperbaric, Drs. Med. R. Rijadi S., Phys. Naval Health Institute, Surabaya, Indonesia
2Department of Physiology, Hang Tuah University, Surabaya, Indonesia
3Department of Biochemistry, Unit of the Experimental Animal, Airlangga University, Surabaya, Indonesia
4Department of Hyperbaric, Pembangunan Nasional University, Jakarta, Indonesia
5Department of Electrical Engineering, Hang Tuah University, Surabaya, Indonesia
Article history:
Received: 1 January 2019
Accepted: 2 May 2019
DOI 10.5001/omj.2020.08
Hyperbaric Oxygenation;
Hypoxia-Inducible Factor 1;
T-Lymphocytes, Regulator y;
Rheumatoid Factor; Arthritis,
Objectives: We sought to investigate and prove the eect of hyperbaric oxygen therapy
(HBOT) on T helper 17 (17)/regulatory T (Treg) cell polarization through changes
in the expression of hypoxia-inducible factor-1 alpha (HIF-1α) in rheumatoid arthritis
(RA) animal model. Methods: We used antigen and collagen-induced arthritis (ACIA)
as a RA animal model. Sixteen male BALB/c models of ACIA mice were divided
into two groups, the non-HBOT group as the control group and the HBOT group
as the treatment group. Expression of HIF-1α, 17 anti-cluster dierentiation 196
(CD196), and Treg anti-interleukine 2 receptor β-chain cells (IL-2Rβ) in tissue from
the le knee joint tissue were determined histologically. Oxidative stress and systemic
inammation were assessed by levels of superoxide dismutase (SOD), interleukin 17a
(IL-17a), C-reactive protein (CRP), and rheumatoid factor (RF) using the enzyme-
linked immune-sorbent assay. e degree of arthritis was assessed by clinical scoring of
paw swelling and the diameter of paw swelling. Results: We found a signicant decrease
(p < 0.050) in the expression of HIF-1α, 17 (CD196), IL-17a, RF levels, and the
clinical scores and the diameter of paw swelling when comparing both groups. ere
was no signicant decrease in the level of CRP in the treatment group compared to
the control group. e expression of Treg (IL-2Rβ) increased signicantly (p < 0.050)
and the level of SOD increased but not signicantly (p > 0.050) in the treatment group
compared to the control group. Conclusions: HBOT has eects on the polarization
of 17 to Treg through a decrease in expression of HIF-1α in mice with ACIA.
HBOT is recommended for use as a support therapy for RA in combination with
drug therapy.
*Corresponding author:
T H,  .
line component of the defense system against free
radicals or reactive species.12
Interleukin 17a (IL-17a) is an inflammatory
biomarker for RA, which has a strong association
with C-reactive protein (CRP).13 CRP is a member
of the pentraxins protein family, which is composed
of ve 23-kDa subunits and its levels can increase
by 1000-fold or more with infection, inammation,
and tissue injury. CRP levels correlate with morning
stiness, pain, fatigue, grip strength, articular index,
and disability.14
Rheumatoid factor (RF) is the most common
laboratory serologic marker for the diagnosis of
RA.15 Although RF can be detected in patients
with other connective tissue diseases, RF isotypes
are helpful in the management of RA patients
from the time of diagnosis until deciding on the
choice of therapeutic strategy. RF testing in RA
patients has a sensitivity of 60% to 90% and a
specicity of 85%.16
RA causes high-intensity pain and severe
suering because it is oen not diagnosed or treated
quickly enough.17 Joint destruction occurs in the rst
six months aer illness, and permanent defects occur
two to three years later if le untreated.18 Extra-
articular manifestations of RA occur in 17.8–40.9%
of RA patients and 1.5–21.5% are usually associated
with increased morbidity and mortality such as
cardiopulmonary and kidney due to developing the
disease itself or the eects of the drugs given.19,20
Years of aggressive treatment are needed to control
symptoms, manage pain, and stop the development
of RA. Standard therapy in the form of drugs and
even surgery has not provided optimal results.21
Hyperbaric oxygen therapy (HBOT) is based
on administering pure oxygen to the patient while
undergoing increased ambient pressure.22 HBOT
can be a new breakthrough for creating appropriate
treatment strategies and reducing the adverse eects
of the drugs used, so HBOT research on RA needs
to be developed again. e Naval Health Institute
of the Indonesian Navy has used HBOT to treat
diving cases of decompression sickness, arterial gas
embolism, and gas poisoning, and even as an adjunct
therapy in some cases of clinical diseases such as
wound healing, diabetes mellitus with gangrene gas,
and osteomyelitis. Several studies have shown that
HBOT has a specic mechanism that can reduce
inflammation, but the mechanism of reducing
arthritis in RA is still unclear.
We conducted a randomized, control study between
January and April 2018. We used BALB/c mice, male,
weighing 20–30 grams, aged 10–14 weeks, healthy
during the adaptation phase with the characteristics
of clear-eyed, shiny fur, agile movements, and
good feces.
e nature of this experiment was invasive and
fatal to the experimental animals. Random sampling
was used to select 16 mice with collagen-induced
antigen and arthritis (ACIA) from a total of 20. e
selected mice were divided into two groups with
each group consisting of eight mice. e rst group
was the control group (non-HBOT) and the second
group was the treatment group (HBOT).
We used ACIA as an animal model of RA
because ACIA is an animal model that is very similar
to RA in humans. Mice were injected with 100 g
of methylated bovine serum albumin (mBSA) in
50 L phosphate buffer saline (PBS), which was
emulsied with 50 L complete Freund adjuvant
subcutaneously and 200 ng of Bordetella pertussis
toxin (PTx) intraperitoneally.
Seven days later, mice were injected with 50 g
mBSA and 100 g collagen type II (CI I) in 50 L PBS
were emulsied with 50 L of incomplete Freund
adjuvant (IFA) and 200 ng PTx subcutaneously.
On day 14 of the study, mice were injected with 50
g mBSA and 100 g CII in 50 L PBS emulsied
with 50 L IFA subcutaneously and 200 ng PTx
intraperitoneally. On day 28 of the study, mice were
induced with 50 g mBSA dissolved in 20 µL PBS
into the le cavity of the knee joint intra-articular
(ipsilateral) and the right knee cavity (contralateral)
was injected with 20 L PBS intraarticularly.
Twenty-one days later (day 49 of the study), we
got research animals with the characteristics of RA
disease (ACIA animal models).
We used Treatment Table 9 (USN TT9), the
hyperbaric oxygen table dosing protocol developed
by the United States Navy (USN). e treatment
group was given normal air exposure for 10 minutes
at 2.4 atmospheres absolute (ATA) pressure. en
given oxygen exposure of 100% 3–4 L/min for
90 minutes divided by 3 × 30 minutes intervals 2
× 5 minutes breathing with normal air at 2.4 ATA
pressure. After that, the pressure was reduced to
1 ATA while breathing normal air without using
oxygen for 10 minutes. e treatment group received
HBOT for 10 consecutive days.
T H,  .
All mice were anesthetized with ketamine (300
mg/kg body weight + xylazine 40 mg/kg body
weight) intraperitoneally aer 30 minutes of exposure
to HBO. Blood and joint tissue samples were taken
aer 10 minutes to ensure no pain response. Blood
was taken using a syringe on the heart ventricle for
enzyme-linked immune-sorbent assay (ELISA)
examination, and synovial tissue was taken by using a
scalpel for immunohistochemical examination. e
mice were killed by neck dislocation.
The expression of HIF-1α was determined
using the anti-HIF-1α mouse monoclonal
immunoglobulin G1 (IgG1) antibody, the anti-
cluster differentiation 196 (CD196) mouse
monoclonal IgG1 antibody for the expression of
17, and anti-interleukine 2 receptor β-chain cells
(IL-2Rβ) mouse monoclonal IgG2b antibody (all
from Santa Cruz Biotechnology, Inc., Santa Cruz,
CA) for expression of Treg. We used the avidin-
biotin complex for staining. Immunoexpression was
calculated from the average number of brown cells
in ve large visual elds at 400 × magnication on a
light microscope.
e level of serum RF was measured using IgG
RF Mouse ELISA kit (LifeSpan BioSciences, Inc.,
USA). e level of serum CRP was measured using
mouse CRP antibody kit (LifeSpan BioSciences,
Inc., USA), and level of IL-17a in plasma was
measured using mouse IL-17a antibody (Bioassay
Technology Laboratory system, Korain Biotech
Co., Ltd, Shanghai, China) with an enzyme-linked
immunosorbent assays (ELISA) reader (Zenix-320
microplate reader). e examination of plasma SOD
levels was measured using a mouse SOD ELISA kit
(LifeSpan BioSciences, Inc., USA) with an ELISA
reader (Spectrophotometer Zhimadzu) analyzers.
e concentrations of RF (IU/mL), CRP (g/mL),
IL-17a (ng/mL), and SOD (L/mL) captured were
Figure 1: Immunohistochemical staining of hypoxia-inducible factor-1α (HIF-1α) in the (G1) non-
hyperbaric oxygen therapy (HBOT) and (G2) HBOT groups. Living cells that expressed the HIF-1α protein
(positive cells) were stained brown and blue cells (hematoxylin stain) showed no expression of the HIF-1α
protein. Magnication (a) = 50 ×, (b) = 400 ×.
T H,  .
determined by measuring absorbance at 450 nm
using a spectrophotometer.
e degree of arthritis was assessed by clinical
scoring of paw swelling and the diameter of the paw
was measured by digital calliper (Mitutoyo, Japan).
e clinical scoring of the paw was graded as follows:
0 = normal and no swelling; 1 = erythema and mild
edema; 2 = erythema and moderate edema; 3 =
erythema and severe edema; 4 = maximal swelling
and deformation leading to incapacitated limb. e
calliper was placed across the paw at widest point
with a level of accuracy up to 0.05 mm (the number
of strips on the slider scale was 20 so that 1 mm: 20
= 0.05 mm). e values were expressed as the mean
of the two paw diameters of mice.
All data were analyzed using SPSS Statistics
(IBM Corp. Released 2013. IBM SPSS Statistics
for Windows, Version 22.0. Armonk, NY: IBM
Corp.). All values were expressed as mean±standard
deviations (SD). A value of p < 0.050 was considered
statistically signicant.
e normality test, using the Shapiro-Wilk test showed
the expression of HIF-1α, CD196, IL-2Rβ, SOD levels,
IL-17a, CRP, RF, clinical scoring of paw swelling, and
diameter of paw swelling had normal distribution (p >
0.050). e results of Lavene test showed expression
of HIF-1α, SOD levels, IL-17a, RF, and the clinical
scoring of paw swelling and the diameter of paw
swelling had homogeneous variance (p > 0.050), but
the expression of CD196, IL-2Rβ, and the level of CRP
did not have homogeneous variance (p < 0.050).
The independent t-test showed there was a
signicant decrease in the expression of HIF-1α in
HBO group (8.7±2.2, p < 0.001) compared to non-
HBO group (69.9±3.1, p < 0.050) [Figure 1].
Figure 2: Immunohistochemical staining of anti-cluster dierentiation 196 (CD196) in the (G1) non-
hyperbaric oxygen therapy (HBOT) and (G2) HBOT groups. Living cells that expressed the CD196 protein
(positive cells) were stained brown and blue (hematoxylin stain) cells showed no expression of the CD196
protein. Magnication (a) = 50 ×, (b) = 400 ×.
T H,  .
The Mann-Whitney test determined that the
expression of CD196 also decreased signicantly in
the HBO group (4.8±1.4, p < 0.001) compared to
non-HBO group (40.0±4.7, p < 0.050) [Figure 2].
e Mann-Whitney test showed the expression
of IL-2Rβ increased signicantly in the HBO group
(5.0±1.3, p < 0.001) compared to the non-HBO
group (48.2±17.9, p < 0.050) [Figure 3].
e dierences in the results of oxidative stress,
systemic inammation, and degree of arthritis in
experimental groups are shown in Table 1. In the
independent t-test showed there was no signicant
Table 1: Dierences of the results of systemic inammation, oxidative stress, and degree of arthritis in the
control and treatment groups.
Variables G1 G2 p-value
SOD, L/mL 0.012 ± 0.001 0.014 ± 0.001 0.093
IL-17, ng/mL 0.2 ± 0.0 0.1 ± 0.0 < 0.001
CRP, g/mL 47.3 ± 18.8 40.4 ± 10.0 0.599
RF, IU/mL 0.012 ± 0.001 41.2 ± 6.8 < 0.001
Clinical scoring of paw swelling 13.6 ± 1.9 8.3 ± 1.9 < 0.001
Diameter of paw swelling, mm 6.9 ± 0.4 6.1 ± 0.4 0.001
SOD: superoxide dismutase; IL-17: interleukin 17; C RP: C-reactive protein; RF: rheumatoid factor.
Data shown as mean±SD; p < 0.050 was considered statistically signicant.
G1: non-HBOT group; G2: HBOT group.
Figure 3: Immunohistochemical staining of anti-interleukine 2 receptor β-chain cells (IL-2Rβ) in the (G1)
non-hyperbaric oxygen therapy (HBOT) and (G2) HBOT groups. Living cells that expressed the IL-2Rβ
protein (positive cells) were stained brown and blue cells (hematoxylin stain) showed no expression of the
IL-2Rβ protein. Magnication (a) = 50 ×, (b) = 400 ×.
T H,  .
increase (p = 0.093) in SOD levels, there was a
signicant decrease (p < 0.001) in the level of IL-
17a, RF, and clinical scoring of paw swelling in the
treatment group compared to control group. e
diameter of paw swelling also decreased signicantly
in the treatment group compared to the control
group [Table 1]. ere was no signicant decrease
in CRP levels between the two groups.
Research on RA continues to develop. Research on
the use of antioxidants or antioxidant-containing
foods combined with drugs, such as methotrexate,
and the addition of natural polyphenol antioxidants,
including silibinin can function to increase the
eect of drugs and reduce oxidative stress.23,24 Our
study limited the use of HBOT alone to determine
the eect and basic mechanism of oxygen use on
the improvement of hypoxic cells and to see the
extent of the role of HBOT in polarization or
changing of phenotype from Th17 cells to Treg
cells. In the future, research on the use of HBOT
in combination with drugs, biological agents, or
other antioxidants needs to be considered and
investigated further.
Several HBOT studies on RA have been carried
out. Clinical improvement due to decreased serum
immune complexes and T lymphocyte function was
found in patients with RA aer 21 sessions of HBOT
under 1.7 ATA for 40 minutes.25 HBOT 70% at 1.5
ATA for three hours daily for two weeks reduced
neuropathic pain in eight Sprague-Dawley male
mice RA models.26 In contrast to previous studies,
this study examined the strategy of autoimmune
anti-rheumatic therapy involving polarization of
17 cells (CD196) into Treg (IL-2Rβ) through
changes in expression of HIF-1α aer HBOT. is
study used higher oxygen levels and pressure than
previous studies but was still based on safe doses. It
has been suggested that if the pressure used to deliver
hyperbaric oxygen did not exceed 3 ATA (equivalent
to 20 meters in seawater) and the duration of
treatment for elective therapy did not exceed two
hours then this HBOT was still considered safe.27
is study used HBOT with dosage according
to USN TT9 breathing 100% oxygen for 3 × 30
minutes intervals 2 × 5 minutes breathing normal
air at 2.4 ATA for 10 consecutive days. Higher doses
were expected to provide more optimal results.
Some theories stated that HBOT was considered a
safe treatment modality but carried a risk because
of hyperoxia and increased pressure. HBOT acted
as a chemical agent that could aect the oxidants
and antioxidants system. e main mechanism for
HBOT was based on the generation of intracellular
ROS. Previously, it has been stated that respiration
with high oxygen concentrations and pressure greater
than 1 ATA would increase ROS production.28,29
We thought that HBOT could lead to increased
ROS and oxidative stress if given at excessive
doses; therefore, this study was limited to 10
consecutive days.
Studies of the effects of HBOT on RA on
oxidative stress has also been carried out previously
using oxygen levels and lower pressures compared to
this study.30,31 HBOT increased the SOD activity,
decreased the value of lipoperoxide, and improved
the erythrocyte sedimentation rate and the Lansbury
articular index in patients with RA.30 HBO oxygen
36% at 1.25 ATA for three weeks reduced derivative
reactive oxygen metabolites and CRP in collagen-
induced arthritis type II mice.31
e results of the study on oxidative stress levels
could be seen in SOD levels. The level of SOD
increased but not signicantly in the HBOT group
compared to non-HBOT group. We hypothesized
that HBOT increased ROS production but, if the
level was not excessive, it could be useful because
ROS could also act as a cellular messenger in many
signal transduction pathways and induce other
cytoprotective genes.32,33 is seemingly c ontroversial
eect was strongly inuenced by therapeutic doses,
and the length and interval of exposure. ROS was
related to the amount of oxygen present, but HBOT
paradoxically induced the activity of antioxidant
enzymes such as SOD. e nuclear factor erythroid
2-related factor 2 (Nrf2)/Keap1 pathway was the
main regulator of redox homeostasis. Nrf2 had a
major contribution to the regulation of defense
systems in various antioxidants as a cytoprotective
response to endogenous and exogenous pressures
caused by ROS.34 SOD functioned to suppress or
prevent the formation of ROS in cells by rapidly
neutralizing any molecule with the potential to
develop into free radicals or any free radicals with the
ability to induce other radical production.35 is fact
was consistent with the concept of mitochondrial
hormesis, which states the production of ROS
could induce a positive response that was increased
T H,  .
resistance to stress, and actually cause oxidative stress
to decrease.36
Understanding HIF expression in RA joints
allows us to better understand the level at which
they are activated based on the severity of the disease,
and how it aects certain cell types that contribute
to perpetuating this disease. RA triggers the
accumulation of HIF-1α and HIF-2α chains, so that
the target of RA therapy was HIF-1α and HIF-2α.37
We chose the HIF-1α variable instead of HIF-2α in
this study because a previous study stated that HIF-
1α was widely expressed and was believed to play an
important role in the hypoxic response compared to
HIF-2α.38 Under normoxia or hyperoxia conditions,
HIF-1α was more easily degraded than HIF-2α,
which was more stable.39,40 Aer HBOT, HIF-1α
was hydroxylated by prolyl hydroxylase domain
proteins, recognized by the ubiquitin E3 ligase, and
directed to the proteasome for degradation.41,42
The results of this study showed significant
decreases in HIF-1α and 17 (CD196) expression,
and a signicant increase in the expression of Treg
(IL-2Rβ) in the treatment group compared to the
control group. e mechanism of HBOT hyperoxia
or normoxia aer exposure to HBOT caused HIF-
1α activity to decrease, which caused polarization or
dierentiation of phenotypes from 17 (CD196)
to Treg (IL-2Rβ). Decreasing the expression of HIF-
1α activated FOXP3 gene expression and finally
degraded RORγt in 17/Treg progenitor when
committing to polarization from 17 to Treg so
that the number of 17 (CD196) decreased.
IL-17a levels decreased signicantly and CRP
levels decreased but not signicantly in the treatment
group compared to the control group. This is in
accordance with previous studies that found a
relationship between serum IL-17a levels and CRP.
IL-17a is inducer CRP from mouse smooth muscle
cells and hepatocytes.43,44 CRP levels decreased, but
not signicantly, because many factors also inuence
CRP levels. ROS is also thought to play a role in
increasing CRP levels.45 We suspect that ROS as a
result of exposure to HBOT could also play a role in
CRP metabolism. Increased blood levels of IL-17a
from mice with RA were of limited use as biomarkers
to show disease activity.46
RFs are a family of autoantibodies directed to
the Fc portion of IgG. ey are locally produced
in RA by B cells present in lymphoid follicles and
germinal center-like structures that develop in
inamed synovium.47 ey are heterogeneous and
usually composed of IgM. Because of this, most
assays detect only IgM. RFs are used as a marker in
individuals with suspected RA or other autoimmune
conditions. Detection of IgM RFs is also helpful as a
prognostic index, and some studies have shown that
immunosuppressive treatment can decrease serum
RF levels. However, the clinical usefulness of RFs in
monitoring disease activity and treatment response is
limited. In this study, the level of IgM RF decreased
signicantly in the treatment group compared to the
control group. Decreasing the number of 17 aer
exposure to HBOT caused a signicant decrease in
IL-17a production in the treatment group compared
to the control group. is resulted in a direct decrease
in autoreactive B cell proliferation and a decrease
in dierentiation and plasma cell activity,16 which
resulted in a decrease in the production of RF.
Hypoxia had been shown to induce an
inflammatory response, in this case, ACIA. The
reduction of arthritis clinically after exposure to
HBOT could be seen from the results of clinical
scoring and diameter of paw swelling, which both
decreased significantly in the treatment group
compared to the control group. e decrease in the
amount and function of Th17 caused a decrease
in the production of pro-inammatory cytokines
IL-17a, IL-17f, IL-21, IL-22, interferon γ, and
granulocyte-macrophage-colony-stimulating factor
so the arthritis decreased.48
We recommend the use of HBOT as a supporting
therapy in RA. Our study provides new insights into
therapeutic interventions in human autoimmune
The authors declared no conflict of interests. The Ethics
Committee of Naval Health Institute, Indonesian Navy stated
that this study was feasibly approved (Animal Ethical Clearance
Certificate No.009/AECC/NHI/IX/2017). This study
received support from the Department of Physiology, Faculty
of Medicine, Hang Tuah University, Surabaya, Indonesia;
Department of Hyperbaric, Drs. Med. R. Rijadi S., Phys. Naval
Health Institute, Indonesian Navy, Surabaya, Indonesia; and
Department of Biochemistry, Unit of the Experimental Animal,
Faculty of Medicine, Airlangga University, Surabaya, Indonesia.
is research was funded by the Faculty of Medicine, Hang Tuah
University, Surabaya, Indonesia.
T H,  .
1. Al Saleh J, EL Sayed M, Monsef N, Darwish E. The
prevalence and the determinants of musculoskeletal diseases
in Emiratis attending primary health care clinics in Dubai.
Oman Med J 2016;31(2):117-123.
2. Mohan SK, Priya V. Serum total sialic acid, lipid
peroxidation, and glutathione reductase levels in patients
with rheumatoid arthritis. Turk J Med Sci 2010;40(4):537-
3. Gaafar T, Farid R, Raafat H, Bayoumi F, Gerges B, Rasheed
D. The TH17/Treg imbalance in rheumatoid arthritis
and relation to disease activity. J Clin Cell Immunol
4. Fasching P, Stradner M, Graninger W, Dejaco C, Fessler
J. erapeutic potential of targeting the 17/Treg axis in
autoimmune disorders. Molecules 2017 Jan;22(1):134.
5. Mateen S, Moin S, Khan AQ, Zafar A, Fatima N. Increased
reactive oxygen species formation and oxidative stress in
rheumatoid arthritis. PLoS One 2016 Apr;11(4):e0152925.
6. Saxena R, Suneja S, Saxena R, Sharma D, Lal AM.
Cumulative eect of systemic inammation and oxidative
stress in 40 known cases of active rheumatoid arthritis. Int J
Res Orthop. 2015 Dec;1(1):7-10.
7. Lepetsos P, Papavassiliou AG. ROS/oxidative stress
signaling in osteoarthritis. Biochim Biophys Acta 2016
8. Rajendiran S, Nimesh A, Ananthanarayanan PH, Dhiman
P, Ananthanarayanan PH, Dhiman P, et al; Swetha Kumari
A; Soundararaghavan S. Markers of oxidative stress in
pregnant women with sleep disturbances. Oman Med J
2015 Jul;30(4):264-269.
9. Lakhter AJ, Lahm T, Broxmeyer HE, Naidu SR. Golgi
associated HIF1a serves as a reserve in melanoma cells. J
Cell Biochem 2016 Apr;117(4):853-859.
10. Semenza GL; US National Library of Medicine National
Institutes of Health. Hypoxia-inducible factors: mediators
of cancer progression and targets for cancer therapy. Trends
Pharmacol Sci 2012 Apr;33(4):207-214.
11. Palazon A, Goldrath AW, Nizet V, Johnson RS. HIF
transcription factors, inflammation, and immunity.
Immunity 2014 Oct;41(4):518-528.
12. Fukai T, Ushio-Fukai M. Superoxide dismutases: role in
redox signaling, vascular function, and diseases. Antioxid
Redox Signal 2011 Sep;15(6):1583-1606.
13. Pavlovic V, Dimic A, Milenkovic S, Krtinic D. Serum levels
of IL-17, IL-4, and INFγ in Serbian patients with early
rheumatoid arthritis. J Res Med Sci 2014 Jan;19(1):18-22.
14. Kim KW, Kim BM, Moon HW, Lee SH, Kim HR. Role
of C-reactive protein in osteoclastogenesis in rheumatoid
arthritis. Arthritis Res er 2015 Mar;17(1):41.
15. Shen R, Ren X, Jing R, Shen X, Chen J, Ju S, et al.
Rheumatoid factor, anti-cyclic citrullinated peptide
antibody, c-reactive protein, and erythrocyte sedimentation
rate for the clinical diagnosis of rheumatoid arthritis. Lab
Med 2015;46(3):226-229.
16. Ingegnoli F, Castelli R , Gualtierotti R. Rheumatoid factors:
clinical applications. Dis Markers 2013;35(6):727-734.
17. Hussain W, Noorwali A, Janoudi N, Baamer M, Kebbi
L, Mansafi H, et al. From symptoms to diagnosis: an
observational study of the journey of rheumatoid arthritis
patients in Saudi Arabia. Oman Med J 2016 Jan;31(1):29-
18. Choy E. Understanding the dynamics: pathways involved
in the pathogenesis of rheumatoid arthritis. Rheumatology
(Oxford) 2012 Jul;51(5)(Suppl 5):v3-v11.
19. Vela P. Extra-articular manifestations of rheumatoid
arthritis. EMJ Rheumatol. 2014;1:103-112.
20. Góis M, Carvalho F, Sousa H, Ferreira AC, Sousa J, Nolasco
F. Renal involvement in rheumatoid arthritis: analysis of 53
renal biopsies. Port J Nephrol Hypert 2017;31(1):25-30.
21. Shih YT, Kao TH, Pan HC, Chen HT, Tsou HK. e
surgical treatment principles of atlantoaxial instability
focusing on rheumatoid arthritis. Biomed Res Int
22. Simsek K, Sadir S, Oter S. e relation of hyperbaric oxygen
with oxidative stress - reactive molecules in action. Oxid
Antioxid Med Sci 2015;4(1):17-22.
23. Dar RA, Brahman PK, Khurana N, Wagay JA, Lone ZA,
Ganaie MA, et al. Evaluation of antioxidant activity of
crocin, podophyllotoxin and kaempferol by chemical,
biochemical and electrochemical assays. Arab J Chem 2017
24. Hussain SA, Mortada AH, Jasim NA, Gorial FI. Silibinin
improves the eects of methotrexate in patients with active
rheumatoid arthritis: pilot clinical study. Oman Med J 2016
25. Lukich VL, Poliakova LV, Sotnikova TI, Belokrinitskiĭ DV.
[Hyperbaric oxygenation in the comprehensive therapy of
patients with rheumatoid arthritis (clinico-immunologic
study)]. Fiziol Zh 1991 Sep-Oct;37(5):55-60.
26. Koo ST, Shin YI, Lee DY, Lee CH. e continuance time
of pressure eect in the rat model of complete Freund’s
adjuvant induced arthritis. Pain Physician 2015 Jan-
27. Eggleton P, Bishop AJ, Smerdon GR. Safety and ecacy of
hyperbaric oxygen therapy in chronic wound management:
current evidence. Chronic Wound Care Management and
Research 2015;2:81-93.
28. om SR. Hyperbaric oxygen: its mechanisms and ecacy.
Plast Reconstr Surg 2011 Jan;127(Suppl 1):131S-141S.
29. St. Nikitopoulou T, Papalimperi AH. e inspiring journey
of hyperbaric oxygen therapy, from the controversy to
the acceptance by the scientic community. Health Sci J
30. Kamada T. [Superoxide dismutase and hyperbaric oxygen
therapy of the patient with rheumatoid arthritis]. Nihon
Seikeigeka Gakkai Zasshi 1985 Jan;59(1):17-26.
31. Nagatomo F, Gu N, Fujino H, Okiura T, Morimatsu F,
Takeda I, et al. Eects of exposure to hyperbaric oxygen
on oxidative stress in rats with type II collagen-induced
arthritis. Clin Exp Med 2010 Mar;10(1):7-13.
32. Harch PG. Hyperbaric oxygen in chronic traumatic brain
injury: oxygen, pressure, and gene therapy. Med Gas Res
2015 Jul;5(1):9.
33. Sureda A, Batle JM, Martorell M, Capó X, Tejada S, Tur JA,
et al. Antioxidant response of chronic wounds to hyperbaric
oxygen therapy. PLoS One 2016 Sep;11(9):e0163371.
34. Ma Q. Role of nrf2 in oxidative stress and toxicity. Annu Rev
Pharmacol Toxicol 2013;53:401-426.
35. Bouvier E, Brouillard F, Molet J, Claverie D, Cabungcal J-H,
Cresto N, et al. Nrf2-dependent persistent oxidative stress
results in stress-induced vulnerability to depression. Mol
Psychiatry 2017 Dec;22(12):1701-1713.
36. Naveed S, Aslam M, Ahmad A. Starvation based dierential
chemotherapy: a novel approach for cancer treatment.
Oman Med J 2014 Nov;29(6):391-398.
37. Hua S, Dias TH. Hypoxia-inducible factor (HIF) as a target
for novel therapies in rheumatoid arthritis. Front Pharmacol
2016 Jun;7:184.
38. Shrestha P, Davis DA, Veeranna RP, Carey RF, Viollet
C, Yarchoan R. Hypoxia-inducible factor-1 alpha as a
therapeutic target for primary eusion lymphoma. PLoS
Pathog 2017 Sep;13(9):e1006628.
39. Wilson GK, Tennant DA, McKeating JA. Hypoxia inducible
factors in liver disease and hepatocellular carcinoma: current
understanding and future directions. J Hepatol 2014
40. Deynoux M, Sunter N, Hérault O, Mazurier F. Hypoxia and
hypoxia-inducible factors in leukemias. Front Oncol 2016
41. Unwith S, Zhao H, Hennah L, Ma D. e potential role of
HIF on tumour progression and dissemination. Int J Cancer
2015 Jun;136(11):2491-2503.
T H,  .
42. Fan L, Li J, Yu Z, Dang X, Wang K. e hypoxia-inducible
factor pathway, prolyl hydroxylase domain protein
inhibitors, and their roles in bone repair and regeneration.
Biomed Res Int 2014;2014:239356.
43. Patel DN, King CA, Bailey SR, Holt JW, Venkatachalam
K, Agrawal A, et al. Interleukin-17 stimulates C-reactive
protein expression in hepatocytes and smooth muscle cells
via p38 MAPK and ERK1/2-dependent NF-kappaB and C/
EBPbeta activation. J Biol Chem 2007 Sep;282(37):27229-
44. Siloşi I, Boldeanu MV, Cojocaru M, Biciuşcă V, Pădureanu
V, Bogdan M, et al. e relationship of cytokines IL-13
and IL-17 with autoantibodies prole in early rheumatoid
arthritis. J Immunol Res 2016;2016:3109135.
45. Xu S, Zhao J, Liu J, Gou W, Fibrinopeptide A. Fibrinopeptide
A induces expression of C-reactive protein via the ROS-
ERK1/2/ P38-NF-κB signal pathway in vascular smooth
muscle cells. Cell Physiol Biochem 2018;47(1):266-278.
46. Shao Y, Zhao FQ. Emerging evidence of the physiological
role of hypoxia in mammary development and lactation. J
Anim Sci Biotechnol 2014 Jan;5(1):9.
47. Song YW, Kang EH. Autoantibodies in rheumatoid
arthritis: rheumatoid factors and anticitrullinated protein
antibodies. QJM 2010 Mar;103(3):139-146.
48. Bystrom J, Taher TE, Muhyaddin MS, Clanchy FI, Mangat
P, Jawad AS, et al. Harnessing the therapeutic potential of
17 cells. Mediators Inamm 2015;2015:205156.
... Several studies have shown that HIF-1α is also involved in Th17/Treg regulation, being able to promote immunity mediated by Th17cells [25,26,62]. HIF-1α is required for Th17 differentiation, and its deficiency reduces the differentiation of this lineage [35]. ...
... HIF-1α is required for Th17 differentiation, and its deficiency reduces the differentiation of this lineage [35]. The differentiation of virgin T cells to the Th17 lineage requires the positive regulation of genes involved in glycolysis, where HIF-1 fulfills a critical role in setting the metabolic state needed for Th17 development [10,13,15,46,62]. In fact, when naive T cells are cultivated under hypoxic conditions (5% O 2 , simulating physiological conditions), the differentiation of Th17 is increased, a phenomenon that requires HIF-1α and is induced by the activation of the mammalian target of rapamycin complex 1 (mTORC1) [10]. ...
... It has also been described that mTORC1 positively regulates IL17 expression through different pathways: STAT3, HIF-1α and S6K2 [66]. Moreover, in conditions where the differentiation of T lymphocytes to Th17 is stimulated (IL6 and TGF-β), there is a positive regulation of Stat3-dependent HIF-1α [50,55,62]. ...
Full-text available
Neuroinflammation is a common event in degenerative diseases of the central and peripheral nervous system, triggered by alterations in the immune system or inflammatory cascade. The pathophysiology of these disorders is multifactorial, whereby the therapy available has low clinical efficacy. In this review, it has been postulated the relationship between the deregulation of T helper cells and hypoxia, mainly Th17 and HIF-1α molecular pathways, events that are involved in the occurrence of the neuroinflammation. The clinical expression of neuroinflammation is included in prevalent pathologies such as multiple sclerosis, Guillain-Barré syndrome, and Alzheimer’s disease, among others. In addition, therapeutic targets are analyzed in relation to the pathways which induced neuroinflammation.
... Conversely, when HBO 2 treatment is administered in hypoxic conditions with a derivational elevated HIF-1α, HBO 2 treatment decreased the disease-mediated high levels of HIF-1α [61,119,[129][130][131][132][133][134][135][136][137][138][139]. The evaluation of studies performed in conditions of relative hypoxia secondary to inflammation indicates that the effect of HBO 2 on HIF-1α protein expression is dependent on the number of HBO 2 sessions administered, with HBO 2 having an increasing effect when administered in up to five sessions [140][141][142][143], and treatment with more than six sessions having a decreasing effect under these conditions [47,120,[144][145][146][147][148][149][150][151][152][153][154][155][156]. However, six study results were not supportive of this trend [117,140,141,[157][158][159]. ...
Full-text available
The perception of sepsis has shifted over time; however, it remains a leading cause of death worldwide. Sepsis is now recognized as an imbalance in host cellular functions triggered by the invading pathogens, both related to immune cells, endothelial function, glucose and oxygen metabolism, tissue repair and restoration. Many of these key mechanisms in sepsis are also targets of hyperbaric oxygen (HBO2) treatment. HBO2 treatment has been shown to improve survival in clinical studies on patients with necrotizing soft tissue infections as well as experimental sepsis models. High tissue oxygen tension during HBO2 treatment may affect oxidative phosphorylation in mitochondria. Oxygen is converted to energy, and, as a natural byproduct, reactive oxygen species are produced. Reactive oxygen species can act as mediators, and both these and the HBO2-mediated increase in oxygen supply have the potential to influence the cellular processes involved in sepsis. The pathophysiology of sepsis can be explained comprehensively through resistance and tolerance to infection. We argue that HBO2 treatment may protect the host from collateral tissue damage during resistance by reducing neutrophil extracellular traps, inhibiting neutrophil adhesion to vascular endothelium, reducing proinflammatory cytokines, and halting the Warburg effect, while also assisting the host in tolerance to infection by reducing iron-mediated injury and upregulating anti-inflammatory measures. Finally, we show how inflammation and oxygen-sensing pathways are connected on the cellular level in a self-reinforcing and detrimental manner in inflammatory conditions, and with support from a substantial body of studies from the literature, we conclude by demonstrating that HBO2 treatment can intervene to maintain homeostasis.
... Additionally, hypoxia not only induces ROS accumulation but also induces high expression of HIF-1a (64). Hyperbaric oxygen therapy reduces the levels of IL-17a, CRP, and rheumatoid factor in CIA mice by regulating the expression of HIF-1a and promotes the differentiation of Tregs, alleviating oxidative stress and inflammatory response (65). CD3 + T-cells and CD68 macrophages cultured in a hypoxic environment exhibit a stronger inflammatory response (21), confirming the critical role of hypoxia in immune inflammation in RA (27). ...
Full-text available
Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial inflammation, pannus formation, and bone and cartilage damage. It has a high disability rate. The hypoxic microenvironment of RA joints can cause reactive oxygen species (ROS) accumulation and mitochondrial damage, which not only affect the metabolic processes of immune cells and pathological changes in fibroblastic synovial cells but also upregulate the expression of several inflammatory pathways, ultimately promoting inflammation. Additionally, ROS and mitochondrial damage are involved in angiogenesis and bone destruction, thereby accelerating RA progression. In this review, we highlighted the effects of ROS accumulation and mitochondrial damage on inflammatory response, angiogenesis, bone and cartilage damage in RA. Additionally, we summarized therapies that target ROS or mitochondria to relieve RA symptoms and discuss the gaps in research and existing controversies, hoping to provide new ideas for research in this area and insights for targeted drug development in RA.
... [17] In addition, HBO affects the M1 to M2 phenotypic shift by decreasing the expression of HIF-1α while increasing the production of IL-10, thereby reducing arthritis in collagen-induced arthritis. [18] We expect HBO to have benefit in peripheral neuropathy as well. ...
Full-text available
Acute motor axonal neuropathy (AMAN) is a rare immune-mediated disorder characterized by acute flaccid paralysis with elevated levels of GM1 antibodies. It is also known as a subtype of the Guillain-Barre syndrome (GBS) and develops since antigen s serve as antibodies in the spinal cord. We report a case diagnosed as AMAN with symptoms of ascending limb symmetrical weakness. A neurological examination revealed a flaccid paralysis with multiple cranial nerve palsies. Electromyography showed an axonal type of GBS. The patient refused bone marrow fluid aspiration. Intravenous immunoglobulin was administered at the high care unit. Unfortunately, despite the standard therapy, an optimal recovery was not obtained. Hyperbaric oxygen (HBO) therapy has been known to be common in illnesses and some clinical diseases. Although it has not been indicated for peripheral neuropathy, a remarkable recovery was soon visible in the HBO-treated AMAN case. The HBO mechanisms involved here are anti-inflammation and immunomodulation.
... If ischaemia is an important part of Long COVID, then preventing it (while not mimicking reperfusion) should be of value [1004,1005]. To this end, hyperbaric oxygen therapy [1006][1007][1008] has been recommended, and in some cases found useful in rheumatoid arthritis [1009][1010][1011], acute [1012,1013] and Long COVID [1006,1014]. An alternative involves O 2 nanobubbles [1015]. ...
Full-text available
Ischaemia-reperfusion (I-R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I-R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID. Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities. Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.
... Inflammatory cells inhabiting the synovial joint develop an inflammatory milieu in the extracellular matrix that induces cellular infiltration and generation of reactive oxygen species (ROS), and consequently, leading to the development of oxidative stress and state of hypoxia [58,59]. Additionally, the free radicals induce a metabolic shift in RASFs, thus disturbing the homeostasis leading to the damage of the basic articular structures [60]. ...
Full-text available
Enhancement of glycolysis and glutaminolysis are the two most common modalities associated with metabolic reprogramming in rheumatoid arthritis (RA). This enhancement is concomitant to the upregulation of hexokinase 2 (HK2) and glutaminase 1 (GLS1). Hence, the current study was undertaken to identify potential phytobiological inhibitors against HK2 and GLS1, from Dracaena (Sansevieria) trifasciata, an indigenous ethnomedicinal plant found in Pakistan, using computational analysis. Phytobiologics from Dracaena trifasciata were assessed for their ability to co-inhibit HK2 and GLS1 via molecular docking and molecular dynamics simulations. The results underscored seven phytobiologics with promising binding affinities for both HK2 and GLS1. Molecular dynamics simulations further elucidated that all seven identified phytobiologics inhibited HK2 by forming stable complexes but only five amongst the seven had the potential to form stable complexes with GLS1 in real time, thereby implying the potential of co-inhibition for these five compounds. Compound 28MS exhibited an equally strong binding profile for both HK2 (−8.19 kcal/mol) and GLS1 (−8.99 kcal/mol). Furthermore, it exhibited a similar trend in stability during simulation for both targets. Our results serve as a primer for a more lucid understanding towards co-inhibition of HK2 and GLS1 using multiple computational approaches. The identified phytobiologics should undergo in-vitro and in-vivo validation to corroborate their therapeutic potential in RA.
... Research by Harnanik et al. shown that HBO treatment has effects on the polarization of Th17 to Treg through a decrease in expression of HIF-1α in mice with antigen and collagen-induced arthritis (ACIA). The conclusion of the aforementioned authors is that HBO treatment can be good supporting therapy for RA in combination with drug therapy [28]. Data from the literature indicate the therapeutic pathway of ADMSCs in OA by paracrine action with the secretion of anti-inflammatory factors [29]. ...
Full-text available
The beneficial effects of HBO in inflammatory processes make it an attractive type of treatment for chronic arthritis. In addition, the effects of combination therapy based on adipose stem cells and HBO on OA progression have not been fully investigated. The current study explored the efficacy of intra-articular injection of allogeneic adipose-derived mesenchymal stem cells (ADMSCs) combined with hyperbaric oxygenation treatment (HBO) in a rat osteoarthritis (OA) model. The rat OA model was induced by intra-articular injection of monoiodoacetate (MIA) and 7 days after application of MIA rats were divided into five groups: healthy control (CTRL), osteoarthritis (OA), ADMSCs (ADS), the HBO+ADS21day and HBO+ADS28day groups. A single dose of 1 × 106 allogeneic ADMSCs suspended in sterile saline was injected into the knee joint alone or in combination with HBO treatment. Rats were sacrificed at 3 or 4 weeks after MIA injection. Treatment outcomes were evaluated by radiographic, morphological and histological analysis and by specific staining of articular cartilage. We also measured the level of inflammatory and pro/antioxidative markers. We confirmed that combined treatment of ADMSCs and HBO significantly improved the regeneration of cartilage in the knee joint. Rtg score of knee joint damage was significantly decreased in the HBO+ADS21day and HBO+ADS28day groups compared to the OA. However, the positive effect in the HBO+ADS28day group was greater than the HBO+ADS21day group. The articular cartilage was relatively normal in the HBO+ADS28day group, but moderate degeneration was observed in the HBO+ADS21day compared to the OA group. These findings are in line with the histopathological results. A significantly lower level of O2−. was observed in the HBO+ADS28day group but a higher NO level compared to the HBO+ADS21day group. Moreover, in the HBO+ADS28day group significantly higher concentrations of IL-10 were observed but there was no significant difference in proinflammatory cytokine in serum samples. These results indicate that a single intra-articular injection of allogeneic ADMSCs combined with HBO efficiently attenuated OA progression after 28 days with greater therapeutic effect compared to alone ADMSCs or after 3 weeks of combined treatment. Combined treatment might be an effective treatment for OA in humans.
... Rheumatoid arthritis (RA) is a systemic heterogeneous autoimmune disease of unknown etiology mainly manifested by chronic inflammatory polyarthritis [1]. It is characterised by T-lymphocyte infiltration-based chronic synovitis that eventually leads to arthritis and bone destruction [2]. In recent years, with the discovery of T-helper ( ) cells in the CD4 + T-cell compartment, the roles of these cells in RA have been unveiled. ...
Full-text available
Yunnan Baiyao (YNB) is a traditional Chinese medicine that possesses anti-inflammatory effects. Previously, we have demonstrated the effects of YNB in rheumatoid arthritis (RA) animal models; however, the underlying mechanisms are unclear. In the present study, we aimed to investigate the effects of YNB on the T-helper (Th)17/T-regulatory (Treg) cell balance in a collagen-induced arthritis rat model orally administrated YNB or methotrexate, a widely used therapeutic agent for treating RA. Our results showed that YNB treatment significantly decreased the voix pedis thickness and joint functionality scores and alleviated joint histopathology in these rats. These YNB-induced effects were achieved by decreasing the number of Th17 cells and increasing that of Treg cells in the spleen. Moreover, the interleukin- (IL-) 17 level considerably decreased in the serum of YNB-treated rats, whereas the IL-10 level significantly increased. Furthermore, YNB could inhibit RANKL-induced osteoclast formation by regulating the tumor necrosis factor receptor-associated factor 6/NF-κB/nuclear factor of the activated T-cell pathway. In summary, our study shows that YNB exhibits antiarthritic activity by decreasing the ratio of Th17/Treg cells, regulating the cytokine balance, and inhibiting osteoclast activation, providing an experimental basis that supports the use of this traditional Chinese medicine for the clinical treatment of RA.
... HIF-1 is widely involved in many cell signaling pathways correlated with oxygen perception and response and is identified as the transduction center of hypoxia signals regulating [32]. It was found in several studies that HIF-1 can impact the immune imbalance of Th17/Treg cells through mediating the Th17/Treg cell expression, thereby causing the occurrence of autoimmune diseases [33]. Phosphatidylinositol-3 kinase (PI3K) can be activated under hypoxia and bind to downstream protein kinase B (Akt) to phosphorylate Akt. ...
Full-text available
Sjögren’s syndrome (SS) which could lead to a disorder of our immune system is a chronic autoimmune disease characterized by invading exocrine glands such as salivary glands and lacrimal glands and other exocrine glands. Its common symptom is dry mouth and dry eyes, often accompanied by a large number of lymphocyte infiltrations and can involve other organs to cause complex clinical manifestations. In this study, we aimed at investigating the effect of QZF in SS, identifying the molecular mechanism in modulating autoimmune response, and determining the important roles of these factors’ function as a modulator in the pathogenesis of SS. The NOD mice were utilized to establish the rats’ model of Sjögren’s syndrome. After 10 weeks’ hydroxychloroquine and QZF in different dose interference, submandibular gland tissue was collected. The therapeutic effect of QZF on SS rats was identified, and the results suggest the comparable potential to hydroxychloroquine. In submandibular gland tissue, interleukin- (IL-) 17 was significantly lower in high-dose QZF than that in SS rats and the focal lymphocytes were highly attenuated. Moreover, we found that PI3K/Akt signals were activated and the downstream HIF-1α/VEGF signals were enhanced in SS rats whose protein expression could be inhibited by QZF treatment. In addition, QZF could modulate autophagy in submandibular gland tissue and then inhibit the inflammation response and therefore facilitate the tissue repair.
... Furthermore, long-term exposure to HBOT was proven to supress the development of autoimmune symptoms, including proteinuria, facial erythema and lymphadenopathy [126]. In the same manner, the use of HBOT in early and middle stage of disease mice also show a significant increase in survival with a decrease in inflammatory cells, anti-dsDNA antibody titers, and amelioration of immune-complex deposition in comparison to later stage of disease [127] The use of HBOT has also proven its efficacy on rheumatoid arthritis, particularly due to the polarization of Th17 cells to T reg, with a significative reduction of cell hypoxia [128]. ...
Full-text available
Hyperbaric oxygen therapy (HBOT) consists of using of pure oxygen at increased pressure (in general, 2–3 atmospheres) leading to augmented oxygen levels in the blood (Hyperoxemia) and tissue (Hyperoxia). The increased pressure and oxygen bioavailability might be related to a plethora of applications, particularly in hypoxic regions, also exerting antimicrobial, immunomodulatory and angiogenic properties, among others. In this review, we will discuss in detail the physiological relevance of oxygen and the therapeutical basis of HBOT, collecting current indications and underlying mechanisms. Furthermore, potential areas of research will also be examined, including inflammatory and systemic maladies, COVID-19 and cancer. Finally, the adverse effects and contraindications associated with this therapy and future directions of research will be considered. Overall, we encourage further research in this field to extend the possible uses of this procedure. The inclusion of HBOT in future clinical research could be an additional support in the clinical management of multiple pathologies.
Full-text available
Background/aims: Atherosclerosis is a chronic inflammatory disease in the artery walls. Fibrinopeptide A (FPA) is a biomarker of the activation of coagulation system, and a high concentration of FPA in blood occurs in patients with ischemic heart disease etc. However, there exist few studies on the pathological effects of FPA in cardiovascular system. Therefore, the present study examined the effect of FPA on CRP expression in VSMCs and the molecular mechanisms. Methods: mRNA and protein expression was identified by quantitative real-time PCR and Western blot, respectively. Reactive oxygen species (ROS) and the immunofluorescence staining were observed by a fluorescence microscope. Plasma FPA and CRP level was determined by ELISA. Results: FPA induced the expressions of CRP, IL-1β and IL-6 in VSMCs, and anti-IL-1β and anti-IL-6 neutralizing antibodies partially reduced FPA-induced CRP expression in VSMCs. The subchronic administration of FPA to rats increased FPA level in plasma and CRP expression in the aortic artery walls. The further studies showed that FPA promoted superoxide anion generation in VSMCs. Antioxidant NAC antagonized FPA-stimulated superoxide anion generation and inhibited FPA-induced CRP expression in VSMCs. FPA activated ERK1/2 and p38 phosphorylation, and PD98059 and SB203580 reduced FPA-induced CRP expression. Moreover, NAC inhibited the activation of ERK1/2 and p38. In addition, FPA enhanced NF-κB level in the nuclei of VSMCs, and PDTC reduced FPA-induced expression of CRP. Conclusions: FPA induces CRP expression in VSMCs via ROS-ERK1/2/p38-NF-κB signal pathway. This finding for the first time provides an experimental evidence for pro-inflammatory effect of FPA.
Full-text available
Primary effusion lymphoma (PEL) is an aggressive B-cell lymphoma with poor prognosis caused by Kaposi’s sarcoma-associated herpesvirus (KSHV). Previous studies have revealed that HIF-1α, which mediates much of the cellular response to hypoxia, plays an important role in life cycle of KSHV. KSHV infection promotes HIF-1α activity, and several KSHV genes are in turn activated by HIF-1α. In this study, we investigated the effects of knocking down HIF-1α in PELs. We observed that HIF-1α knockdown in each of two PEL lines leads to a reduction in both aerobic and anaerobic glycolysis as well as lipid biogenesis, indicating that HIF-1α is necessary for maintaining a metabolic state optimal for growth of PEL. We also found that HIF-1α suppression leads to a substantial reduction in activation of lytic KSHV genes, not only in hypoxia but also in normoxia. Moreover, HIF-1α knockdown led to a decrease in the expression of various KSHV latent genes, including LANA, vCyclin, kaposin, and miRNAs, under both normoxic and hypoxic conditions. These observations provide evidence that HIF-1α plays an important role in PEL even in normoxia. Consistent with these findings, we observed a significant inhibition of growth of PEL in normoxia upon HIF-1α suppression achieved by either HIF-1α knockdown or treatment with PX-478, a small molecule inhibitor of HIF-1α. These results offer further evidence that HIF-1α plays a critical role in the pathogenesis of PEL, and that inhibition of HIF-1α can be a potential therapeutic strategy in this disease.
Full-text available
Background: Rheumatoid arthritis (RA) is a systemic inflammatory disorder characterized by joint inflammation, associated with autoantibody production. Renal involvement arises as a complication of treatment or can be related to the disease itself. Methods: 53 biopsies from patients with RA from 1989 to 2015 were reviewed. Histologic diagnosis, age, gender, duration of RA, drug therapy, renal function, proteinuria and haematuria were analyzed. Results: Amyloidosis was the most common renal histologic pattern (21 patients). Membranous Nephropathy (MN) was found in 12 patients, followed by Mesangial Proliferative Glomerulonephritis (n=4) and Focal and Segmental Glomerulosclerosis (n=4), IgA Nephropathy (n=3), Necrotizing Glomerulonephritis (n=3), Chronic Interstitial Nephritis (n=3), Endocapillary Proliferative Glomerulonephritis (n=2) and Minimal Change Disease (n=1). Amyloidosis correlated with long duration RA (14.9±6.66 years vs 8.84±6.37 years; p
Full-text available
A disruption of the crucial balance between regulatory T-cells (Tregs) and Th17-cells was recently implicated in various autoimmune disorders. Tregs are responsible for the maintenance of self-tolerance, thus inhibiting autoimmunity, whereas pro-inflammatory Th17-cells contribute to the induction and propagation of inflammation. Distortion of the Th17/Treg balance favoring the pro-inflammatory Th17 side is hence suspected to contribute to exacerbation of autoimmune disorders. This review aims to summarize recent data and advances in targeted therapeutic modification of the Th17/Treg-balance, as well as information on the efficacy of candidate therapeutics with respect to the treatment of autoimmune diseases.
Full-text available
We analyzed the effects of the clinical hyperbaric oxygen therapy (HBOT) on the plasma antioxidant response and levels of endothelin-1, Interleukine-6 (IL-6) and vascular endothelial growth factor (VEGF) in patients with chronic wounds (20.2±10.0 months without healing). They received 20 HBOT sessions (five sessions/week), and blood samples were obtained at sessions 1, 5 and 20 before and 2 hours after the HBOT. An additional blood sample was collected 1 month after wound recovery. Serum creatine kinase activity decreased progressively in accordance with the wound healing. Plasma catalase activity significantly increased after the first and fifth sessions of HBOT. Plasma myeloperoxidase activity reported significantly lower values after sessions. Plasma VEGF and IL-6 increased after sessions. Endothelin-1 levels were progressively decreasing during the HBOT, being significant at the session 20. Plasma malondialdehyde concentration was significantly reduced at the last session. Both creatine kinase activity and malondialdehyde levels were maintained lower 1 month after wound recovery respect to initial values. In conclusion, HBOT enhanced the plasma antioxidant defenses and may contribute to activate the healing resolution, angiogenesis and vascular tone regulation by increasing the VEGF and IL-6 release and the endothelin-1 decrease, which may be significant factors in stimulating wound healing.
Full-text available
Stressful life events produce a state of vulnerability to depression in some individuals. The mechanisms that contribute to vulnerability to depression remain poorly understood. A rat model of intense stress (social defeat (SD), first hit) produced vulnerability to depression in 40% of animals. Only vulnerable animals developed a depression-like phenotype after a second stressful hit (chronic mild stress). We found that this vulnerability to depression resulted from a persistent state of oxidative stress, which was reversed by treatment with antioxidants. This persistent state of oxidative stress was due to low brain-derived neurotrophic factor (BDNF) levels, which characterized the vulnerable animals. We found that BDNF constitutively controlled the nuclear translocation of the master redox-sensitive transcription factor Nrf2, which activates antioxidant defenses. Low BDNF levels in vulnerable animals prevented Nrf2 translocation and consequently prevented the activation of detoxifying/antioxidant enzymes, ultimately resulting in the generation of sustained oxidative stress. Activating Nrf2 translocation restored redox homeostasis and reversed vulnerability to depression. This mechanism was confirmed in Nrf2-null mice. The mice displayed high levels of oxidative stress and were inherently vulnerable to depression, but this phenotype was reversed by treatment with antioxidants. Our data reveal a novel role for BDNF in controlling redox homeostasis and provide a mechanistic explanation for post-stress vulnerability to depression while suggesting ways to reverse it. Because numerous enzymatic reactions produce reactive oxygen species that must then be cleared, the finding that BDNF controls endogenous redox homeostasis opens new avenues for investigation.Molecular Psychiatry advance online publication, 20 September 2016; doi:10.1038/mp.2016.144.
Full-text available
Aims. In the present study, we aimed to assess the concentrations of IL-13 and IL-17 in serum of patients with early rheumatoid arthritis (eRA), the investigation of correlation between the concentrations of these cytokines and disease activity score, and the concentration of some autoantibodies and the evaluation of the utility of IL-13 and -17 concentration measurements as markers of disease activity. Materials and Methods . Serum samples were collected from 30 patients and from 28 controls and analysed parameters. Results . The serum concentrations of IL-13, IL-17, anti-CCP, and IgM-RF were statistically significantly higher in patients with eRA, compared to the controls. IL-13 concentrations in the severe and moderate groups with eRA were statistically higher than in the mild and control groups. Also, in the case of IL-17, serum concentrations increased proportionally with the disease activity of eRA. We observe that concentrations of IL-13 and -17 did not correlate with autoantibodies. IL-17 concentration significantly positively correlated with CRP, while IL-13 concentration significantly negatively correlated with CRP. Disease activity score, DAS28, was strongly positively correlated with levels of ESR and weakly positively correlated with concentrations of anti-RA33 autoantibodies. IL-13 has a higher diagnostic utility than IL-17, CRP, ESR, IgM-RF, and anti-CCP as markers of disease activity. Conclusions . The presence of higher IL-13 and IL-17 serum levels in patients, compared with those of controls, confirms that these markers, found with high specificity, might be involved in the pathogenesis of eRA. IL-13 and IL-17 might be of better usefulness in the prediction of eRA activity status than IgM-RF and anti-CCP.
Full-text available
Objectives: Our study sought to evaluate the effects of silibinin in patients with active rheumatoid arthritis (RA) treated with methotrexate (MTX). Methods: We conducted a randomized multi-center, double-blind, placebo-controlled clinical trial over a 16-week treatment period at the Al-Sader and Baghdad Teaching Hospitals in Najaf and Baghdad, respectively. A total of 60 patients (30 of each sex) with active RA, already maintained on 12 mg MTX weekly for at least three consecutive months, were included in the study. Patients were randomly allocated to receive either 120 mg silibinin twice daily or a placebo, combined with their regular MTX regimen. The patients were evaluated by measuring disease activity score using the 28-joint Disease Activity Score, Simple Disease Activity Index, and Health Assessment Questionnaire-Disability Index scores at the start and end of the study. Blood samples were evaluated for the erythrocyte sedimentation rate (ESR), hemoglobin (Hb), high-sensitivity C-reactive protein (hs-CRP), creatine kinase (CK), anti-cyclic citrullinated peptide (CCP), and the serum cytokine levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-8, IL-10, and IL-2. Results: Silibinin significantly decreases the already elevated clinical scores compared to placebo treatment. ESR, IL-8, IL-6, TNF-α, anti-CCP, hs-CRP levels were significantly reduced. Additionally, the use of silibinin significantly increases Hb, IL-10, and IL-2 levels. Conclusion: Silibinin may improve the effects of MTX on certain biochemical and clinical markers of patients with active RA.
Full-text available
Hypoxia is an important micro-environmental characteristic of rheumatoid arthritis (RA). Hypoxia-inducible factors (HIF) are key transcriptional factors that are highly expressed in RA synovium to regulate the adaptive responses to this hypoxic milieu. Accumulating evidence supports hypoxia and HIFs in regulating a number of important pathophysiological characteristics of RA, including synovial inflammation, angiogenesis and cartilage destruction. Experimental and clinical data have confirmed the upregulation of both HIF-1α and HIF-2α in RA. This review will focus on the differential expression of HIFs within the synovial joint and its functional behaviour in different cell types to regulate RA progression. Potential development of new therapeutic strategies targeting HIF-regulated pathways at sites of disease in RA will also be addressed.