Transcript Burn Wound Healing

Plant resources -- Aloe
052991 黄力维
052983 徐雍羽
Introduction
Kingdom:
Plantae(植物界)
Division:
Magnoliophyta（木兰门）
Class:
Liliopsida（百合纲）
Order:
Asparagales（天门冬目）
Family:
Asphodelaceae（日光兰科）
Genus:
Aloe
Morphological Feature：
Most Aloes have a rosette of
large, thick, fleshy leaves.
The leaves are often lance(茅)shaped with a sharp apex（顶点）
and a spiny（多针刺的） margin.
Aloe flowers are tubular（管状
的）, frequently Brown, pink or
red and are born on densely
clustered, simple or branched
leafless stems.
Many species of Aloe are
seemingly stemless, with the
rosette growing directly at
ground level; other varieties
may have a branched or unbranched stem from which the
fleshy leaves spring. They vary
in disecis from grey to bright
green and are sometimes striped
（有条纹的） or grasped.
Introduction
Aloe vera (Aloe vera
Linn, synonym: aloe
vera barbadensisMill.) is
in family Liliaceae,
which is a tropical plant
easily grown in hot and
dry climates.
• Numerous cosmetics
and medicinal products
are made from the
mucilaginous tissue,
called aloe vera gel,
located in the center of
the aloe vera leaf.
• Aloe vera gel has been
used for many
indications since the
Roman era or even long
before.
Aloe Extracts
• Burn wound healing
• Antifungal
• Anti-diabetes
• anti-obesity
• Anti-inflammation
• Burn wound healing is one
of major indications of aloe
vera gel use in many
countries.
• Existing evidence
demonstrates that aloe vera
used in a variety of dosage
forms might be effective in
shortening the duration of
wound healing in first to
second degree burns, and it
tended to increase rate of
success to healing and rate
of epithelialization.
Burn Wound Healing
• These effects might be due to several mechanisms
including an increasing collagen synthesis and rate of
epithelialization by the effect of acemanan
(mannose-6 phosphate) to stimulate fibroblasts, an
anti-inflammatory effect, an antimicrobial effect, and
a moisturizing effect.
• Aloe vera products are also safe for topical use.
There was no withdrawal or serious adverse reaction
reported in the included studies.
Antifungal activity of Aloe vera leaves
• Aloe vera fresh leaves
hydroalcoholic plant extract was
tested against the mycelial growth
of Botrytis gladiolorum, Fusarium
oxysporum f.sp. gladioli,
Heterosporium pruneti and
Penicillium gladioli on Czapek-agar
medium.
• The minimum fungicidal
concentration (MFC) varied
between 80 and 100 μl/ml,
depending on the fungal species.
Aloe Extracts’ Effect On Diabetic
• Extracts of aloe gum effectively increased glucose
tolerance in both normal and diabetic rats.
• The hypoglycemic effect of single dose of the bitter
principle was extended over a period of 24 h with
maximum hypoglycemia observed at 8 h while
chronic administration (exudate twice daily and the
bitter principle once a day for 4 days) showed
maximum reduction in plasma glucose level at the
5th day.
• Hypoglycemic effect of aloe and its bitter principle is
mediated through stimulation of synthesis and/or
release of insulin from the beta-cells of Langerhans.
Aloe Extracts’ Effect On Obesity
• Because of its reputed anti-diabetic activity, scientists have
decided to investigate its effect on obesity.
• The NS2 extract significantly reduced body weight, fat pads
and liver weight, and blood glucose levels compared to the
control and HF-NS1.
• Although NS1 significantly lost body weight, paradoxically
tissue weights and glucose levels were not significantly
different from control rats.
• This data suggests that NS2 extract has both antiobesity and
antidiabetic properties.
Extracts
• Aloe Emodin
• APS-1
• Dihydrocoumarin
• Production of large amounts of TNF has been
implicated in the liver damage during sepsis, viral
hepatitis, alcoholic hepatitis, ischemia-reperfusion
liver injury and fulminant hepatic failure, as well as in
chemical-induced hepatotoxicity. Accordingly, TNF
displayed a direct TNF-R1-dependent toxicity
towards hepatocytes, both in vitro and in vivo
• Aloe emodin inhibited both basal and TNF-triggered
activation of extracellular signal-regulated kinase
(ERK), and a selective blockade of ERK activation
mimicked the cytoprotective action of the drug.
Aloe emodin protects L929 cells from TNFinduced death
Aloe Emodin
• Aloe emodin also has the anticancer effect in
two human liver cancer cell lines, Hep G2 and
Hep 3B.
• It inhibited cell proliferation and induced
apoptosis in both examined cell lines, but with
different the anti-proliferative mechanisms.
Aloe Emodin
• In Hep G2 cells, aloe-emodin induced p53 expression
and was accompanied by induction of p21 expression
that was associated with a cell cycle arrest in G1
phase. In addition, aloe-emodin had a marked
increase in Fas/APO1 receptor and Bax expression.
• In contrast, with p53-deficient Hep 3B cells, the
inhibition of cell proliferation of aloe-emodin was
mediated through a p21-dependent manner that did
not cause cell cycle arrest or increase the level of
Fas/APO1 receptor, but rather promoted aloeemodin induced apoptosis by enhancing expression
of Bax.
Effects of aloe-emodin on the
proliferation inhibition of Hep G2 and
Hep 3B cell lines
APS-1
• APS-1 is a polysaccharide which is isolated from fresh
leaves of Aloe vera.
• It is demonstrated to be free radical scavenging in
superoxide and hydroxyl radical assays, inhibitory to
the copper-mediated oxidation of human low density
lipoprotein (LDL), and protective against hydrogen
peroxide (H2O2)-induced lesion to rat PC12 cell (
pheochromocytoma cell line).
• The result suggested that APS-1 could be of
considerable preventive and therapeutic significance
to some free radical associated health problems such
as coronary heart ailments, Parkinson’s and
Alzheimer’s diseases.
Scavenging activity of APS-1 against superoxide
radical generated in PMS/NADH system with ascorbic
acid as a positive control.
Aloe dihydrocoumarin is
an antioxidant and a
candidate of
immunomodulatory
drug on the immune
system and can balance
physiological reactive
oxygen species (ROS)
levels which may be
useful to maintain
homeostasis.
Machanism of Dihydrocoumarin
It is beneficial in regulating ROS levels by
directly scavenging ROS and promoting the
oxygen production in the respiratory burst of
macrophages. The superoxide anion and
nitric oxide released from respiratory burst
response of macrophages
can kill invading pathogen
or cancer cells in immune
response.
Machanism of Dihydrocoumarin
HSA(human serum albumin), is the most
abundant protein in blood plasma, is the most
important drug carrier protein.
It has a strong affinity for a variety of chemical
species. As a consequence, HSA should play an
important role in the biological fate of
dihydrocoumarin.
REFERENCES
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Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical
University, Kaohsiung 807, Taiwan, ROC Department of Pharmacy, Ta-Jen Institute
of Technology, Ping-Tung 907, Taiwan. The antiproliferative activity of aloe-emodin
is through p53-dependent and p21-dependent apoptotic pathway in human
hepatoma cell lines. Life Sciences 71 (2002) 1879–1892.
Jun H. Wu, Chen Xu, Cheng Y. Shan, Ren X. Tan. Antioxidant properties and PC12
cell protective effects of APS-1, a polysaccharide from Aloe vera var. chinensis. Life
Sciences 78 (2006) 622 – 630.
J.K. Grover *, S. Yadav, V. Vats. Medicinal plants of India with anti-diabetic
potential. Journal of Ethnopharmacology 81 (2002) 81-100.
Oana Rosca-Casian, Marcel Parvu, Laurian Vlase, Mircea Tamas. Antifungal activity
of Aloe vera leaves. Fitoterapia 78 (2007) 219–222.
Ljubica Harhaji, Sanja Mijatovic, Danijela Maksimovic-Ivanic, Dusan Popadic,
Aleksandra Isakovic, Biljana Todorovic-Markovic, Vladimir Trajkovic. Aloe emodin
inhibits the cytotoxic action of tumor necrosis factor. European Journal of
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N.R.S. Sibuyi, D.R. Katerere, T. Boboyi, A.M. Madiehe. Dietary supplementation
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Xiu-Feng Zhang, Ling Xie, Yang Liu, Jun-Feng Xiang, Lin Li, Ya-Lin Tang *. Molecular
interaction and energy transfer between human serum albumin and bioactive
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Ratree Maenthaisong, Nathorn Chaiyakunapruk*, Surachet Niruntraporn, Chuenjid
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