الفهرس 
Chapter I: PsoriasisOnly 14 pages are availabe for public view
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Abstract
Psoriasis is chronic, relapsing, immune- mediated inflammatory
skin disease affecting 1-3% of the world population.
Clinical manifestations of psoriasis are heterogeneous, ranges
from limited to extensive disease. The majority of patients
approximately (80%) have limited disease while approximately (20%)
have extensive disease. The most characteristic lesions consist of red,
scaly sharply demarcated, erythematous papules and plaques present
particularly over extensor surfaces and the scalp. The disease is
variable in extent, duration and periodicity of flares.
The etiology of psoriasis is unknown, but evolving evidence
suggests that it is a complex disorder caused by interaction of multiple
factors includes immunological, environmental and genetic factors.
It has been recognized as a systemic disorders associated with
various comorbidities.
Epidemiological data demonstrate that psoriasis patients suffer
from a spectrum of comorbidities which may be roughly divided into
two types:
(1) Comorbidities due to common pathogenetic mechanisms such
as psoriatic arthritis and Crohn’s disease;
(2) Comorbidities following chronic severe inflammation
characteristic for psoriasis such as cardiovascular disorders and
metabolic syndrome (MS).
It has been identified that MS, which is characterized by the
association of abdominal obesity, atherogenic dyslipidemia,
hypertension, and insulin resistance with or without glucose
intolerance and a pro-inflammatory and pro-thrombotic state, is a risk
factor for cardiovascular disease.
The pathogenesis of metabolic syndrome is supposed to be
related to increased levels of adibocytokines, such as tumor necrosis
factor-α (TNF-α) which induce insuline resistance.
RBP4 belongs to the lipocalin family and is the specific carrier
for retinol in the blood. It delivers retinol from the liver store to the
peripheral tissues.
RBP4 plays a role in regulating the lipid and glucose
metabolism as it causes lipogenesis and insuline resistance. RBP4 was
associated with the component of metabolic syndrome especially with
hypertriglycerydemia, elevated blood pressure and increase total
cholesterol.
The aim of this work was to investigate the role of serum retinol
binding protien 4 in psoriasis pathogenesis.
This prospective study was carried out on 55 patients presented
with chronic plaque psoriasis. They were selected from dermatology
outpatient clinic, Menoufiya University Hospital during the period
from March 2015 to October 2015. All patients were not on any
topical or systemic therapy for at least 6 months before samples
taking. Thirty age, gender and BMI matched apparently healthy
volunteers were also included in this study as a control group. All
studied cases were subjected to complete history taking, clinical and
dermatological examination including assessment of PASI score,
waist circumference measurement, BMI determination and blood
pressure measurement. Venus blood samples (10 ml) were taken after
12 hours overnight fasting and sent to Biochemstry Department,
Faculty of Medicine, Menoufiya University for measuring RBP4 level
by enzyme linked immunosorbent assay (ELISA), lipid profile ( total
cholesterol, triglycerides, high denisty lipoprotien cholesterol ) and
fasting blood glucose.
In the current study, Total cholesterol and triglyceride levels
were significantly higher among cases than among control group (P
<0.001), while HDL-C level was significantly lower among cases than
among control (P <0.001).
Systolic and diastolic blood pressure was significantly higher
among cases than among controls (P < 0.07, P< 0.01).
There was significant difference between cases and controls
regarding blood glucose level, which was significantly higher among
cases than controls (P<0.03).
There was a significant difference between cases and controls
as regarded to metabolic syndrome; 60% of psoriasis patients had
positive metabolic syndrome versus 33.3% of controls had positive
metabolic syndrome.
There was highly significant difference between cases and
controls regarding RBP4 level, which was significantly higher among
cases than in controls (P<0.001).
There was significantly higher PASI score among cases with
high RBP4 than those with low RBP4 (P <0.001).
There was significant association between high RBP4 and low
HDL-C level (P=0.01) and high total cholesterol level (P=0.001).
There was significant positive correlation between RBP4 and
Waist circumference (r=0.21, P=0.05) and PASI score (r=0.81,
P=<0.001).
There was significant negative correlation between RBP4 and
HDL-C level (r=- 0.82, P=<0.001).
There was significant positive correlation between RBP4 and
total cholesterol level(r=- 0.80, P=<0.001) and TG level (r=- 0.68,
P=<0.001).
from this work, we can conclude that the association between
RBP4 and different metabolic comorbidities as dyslipidemia and
metabolic syndrome that linked to psoriasis suggest that RBP4 might
be an adipokine of meaningful role in psoriasis. The mechanisms
through which RBP4 is associated with psoriasis are that RBP4 has
inflammatory role by inducing expression and secretion of proinflammatory
cytokines in primary human macrophages such as TNF-
α and IL-6 which are characteristic for psoriasis and RBP4 is likely to
be associated with vasodilation and angiogenesis in certain
pathological conditions, and angiogenesis has been one of the
fundamental inflammatory responces in the pathogenesis of psoriasis.
Serum RBP4 is positively correlated with the severity of the disease
so, it can be used as a psoriasis severity and prognostic marker.
Further large-scaled studies are recommended to expand and
validate current findings. Study serum RBP4 in other clinical types of
psoriasis is needed. Strict follow up of psoriatic patients even the non
obese ones by regular laboratory investgations for early intervention
of MS, IR and their subsequent health complications is also
recommended.