Efficiency of green tea extacts and its derviaties in the treatment of rabbits skin burns

العناوين الأخرى

فاعلية مستخلص و مشتقات الشاي الأخضر في معالجة حروق جلد الأرانب

مقدم أطروحة جامعية

al-Nmmar, Nuaymah Muhammad Khalifah

مشرف أطروحة جامعية

Atiyyah, Salah Ibrahim
Awad, Muhammad Hammad

أعضاء اللجنة

Muhammad, Ali Sad
al-Ubayd, al-Ubayd Abd al-Rahim

الجامعة

جامعة أم درمان الإسلامية

الكلية

كلية العلوم و التقانة

القسم الأكاديمي

قسم الحيوان

دولة الجامعة

السودان

الدرجة العلمية

ماجستير

تاريخ الدرجة العلمية

2009

الملخص الإنجليزي

Plant extracts have been widely used as topical application for wound healing, anti-aging, and disease treatments.

These plants share a common character ; they produce flavonoid compounds with phenolic structures.

These phytochemicals are highly reactive with other compounds, such as reactive oxygen species and biologic macromolecules, to neutralize free radicals or initiate biological effects.

A short list of phenolic phytochemicals with promising properties to benefit human health includes a group of polyphenol compounds, called catechins, found in green tea.

We summarized the findings of studies using green tea polyphenols as chemopreventive, natural healinagents, and anti-aging agents of burn-wounds.

Green tea is the richest source of polyphenols and terpenes.

Interest in the growing green tea stimulated many studies for protection against several biological alterations including cancer.

These fractions were found to be antioxident through their peroxidase activity, lipoxygenases and cyclooxygenases which are capable of co-oxidizing molecules other than their regular substrates, with the potential for increasing oxidative damage in some tissues.

Green tea polyphenols were found to inhibit cyclooxygenase (COX)-2 and 5-, 12-and 15-lipoxygenase activities in human colon mucosa cells and human colon cancer cells.

Feeding green tea polyphenols to mice inhibited ultraviolet light-induced burn and increases in epidermal COX activity, whereas topical application of green tea and black tea polyphenols inhibited phorbol ester-induced increases in epidermal COX and lipoxygenase activites.

Precancerous lesions of colon mucosa (aberrant crypts) and COX-2 activity were bower in azoxymethane-treated rats given 2 % green tea extract in their drinking water compared with controls.

Burns are a major problem in many developing countries.

Eupolin ointment is a topical agent used in the treatment of soft tissue wounds and burns.

So, the aim of this study is to evaluate the potential and beneficial effect of green tea extract and its derivatives in repairing skin burns in comparison with manufactured.antibiotics For this purpose basic histological methods were used in this study.

The skin is composed of epidermis and dermis.

The epidermis is constructed of large number of polygonal layers of cells darkly stained by hematoxylin and eosin stains.

These layer of cells are invaginated within the dermis forming dermal papillae which are the origin of skin derivatives, glands and/or hairs.A Number of hair roots was found within the loose connective tissues of the dermal structure.

Few of sweat glands were also found and some sebaceous glands were observed.

Studies using green tea extract have shown antimicrobial and anticoagulation effects as well as the promotion of tissue remodeling in the wound healing process.

However, the mechanism by which this agent affects cell involved in the wound healing process is unknown.

In many researches, fibroblasts and endothelial cells, are the two cell types that play a crucial role in wound healing, Enhanced growth of fibroblasts and endothelial cells was found at concentrations of 10 ml and 100 µg / ml of green tea extract.

This was particularly evident in a medium supplemented with only 0.5 % fetal calf serum where the cells were quiescent.

There was no significant damage at these doses to the endothelial cells.

The present study was carried out on fifty premature native rabbits which were obtained from unburied strain of private farm in Sebha District.

The animals were left for one week to be aclamatized and then, were divided into five groups (10 animals each).

The previous groups were divided into two sub-groups (5 animals each) ; five sub-groups burned by direct fire and the other burned by concentrated HCl.

The five groups were, control group (untreated), crude fraction treated group, polyphenol fraction treated group, terpenes extract treated group and antibiotic ointment treated group.

The dorsal skin of the all rabbits were shaved by putting a shaving cream upon the skin for few minutes then the hairs were removed by sweeping the shaving cream with a piece of sponge for several times.

The animals were left for 24 hrs.

and any growing hairs were reshaved again, then they were left for 48 hrs.

to recure any inflammation caused by the shaving cream.

In fire burned groups ; hot glass rod (800C) was put for one minute upon the shaved skin.

This step was repeated 3 times where the hot rod was put onto the same area.

The burned animals were housed separately in partitioned cages to avoid crowding and contamination from each other.

Twelve hours dark / light cycle by sterilization lamps and the treatment started at the next day of burn induction.

In chemical burned groups ; minute drops of concentrated hydrochloric acid (HCL) were spreaded topically upon the shaved skin of the animals in 5 mentioned groups above.

Treatment steps : A-One group with two types of burns was left untreated as a control group.

B-One group was treated by crude extract by spreading a layer over the burn (0.02 ml) two times a day.

C-Minute drops of polyphenols were allowed to cover the burns (0.02 ml) per rabbit a day in two groups.

D-Minute drops of terpenes were allowed to cover the burns (0.02 ml) per rabbit a day in two groups eaflet advise two times a day.

E-Baneocin cream (an Ointment, broad spectrum antibiotic for topical therapy produced by Pharco pharmaceuticals, Egypt.

Under the license of Biochemie GmbH, Vienna, Austria) was spreaded above the burns in a thin layer as Histological technique : After one, 2weeks, 3 weeks,4weeks and 5 weeks of treatment one animal of each group was randomly selected weekly and sacrificed and the burned skin was separated as routine histological methods.

After spreading of concentrated HCl over the shaved dorsal skin of the animals groups, the skin was collectively destructed leaving ulcer-like wounds which become deep through few hours.

The wound became of double area at the second week and then reduced to the minimum volume left burns signs in which no hair grow up.

From the tables of burns parameters, it was observed that the maximum mean of burns area in control group were recorded through the first week observation was 3.99 ± 0.65 cm², but it reduced in other groups, where the smallest value was in terpenes group.

The contractibility rate of control was moderate.

The closure time was between 20 to 25 days while the recovery times were between 18 to22 days.

The hairs were grown at 29 to 32 days in control but at 22-25 in antibiotic group.

These parameters in antibiotic treated groups were significantly different from those of control groups.

The mean burns area was 3.57 ± 0.38 cm² which were reduced significantly to (2.31 ± 0.27 cm²) after the first week of treatment.

This reduction of wound size stayed with high rate leaving many rabbits without burns signs at the beginning of the fifth week of treatment.

The closure time was between 10 days and 13 days.

The recovery time was between 8 days and 10 days.

The hairs grew well at the end of the fifth week.

The crude extract-treated groups were more sensitive than those of treated by polyphonls or terpenes, and run parallel to the antibiotic treated group; however, the contractability rate was lower than the antibiotic treated ones.

The mean volumes of wounds were 3.64 ± 0.72 cm² reduced to 0.58 ± 0.03 cm² at the beginning of the fifth week of treatment, and the recovery time was between 7 to 11 days, whereas the closure time was 10 to 15 days.

The hairs grew from 23 to 25 days of treatment.

Polyphenols and terpenes gave results below the antibiotic and rude extract treated groups.

In closure time, recovery time and growing hair time and they have more mean volume of wounds than antibiotic group.

Worthy, the burn wounds were recovered and contracted to the minimum volumes at the beginning of the fifth week of treatment.

Polyphenols and terpenes groups were closely similar in contractibility time and growing hair time parameter tested in this work.

But the direct fire induced burned wounds were different than those caused by chemical.

By application of different types of treatments the burned wounds reduced in size.

Many of such burns were covered by hard and thick coats.

As mentioned before, certain wounds were still covered by such coats and then the coats were shedding off leaving thin layer of skin.

It was found that all treated groups gave high results as compared with control (untreated) group.

The burns wounds of the control (untreated) group reduced from 4.22 ± 0.92 cm² to 0.92 ± 0.15 cm² at the end of the fifth week of observation.

Some burns were left abnormally skin structure, others gave on hair growth and some became normal with growth.

All types of treatments reduced the wounds to the minimum volume at the beginning of the fifth week, whoever some burns showed no hair growth.

At the third week of treatment the burns reduced to half volume of burns treated by antibiotic and crude extract from 3.66 ± 0.56 and 3.10 ± 0.55cm² to 1.81 ± 0.20 and 1.67 ± 0.19 cm² respectively.

Polyphenols reduced the volumes of burns wounds at lower rate than antibiotic and crude extract.

The contractibility rate of wounds was very high by application of antibiotic and crude extract, while it was high through application of polyphenols and terpenes.

The closure times of wounds were between 15 to 18 days in control group.

These times reduced significantly to 7 to 9 days; 8 to 10 days; 9 to 11 days 10 to 12 days by application of antibiotic, crude extract, polyphones and terpenes groups, respectively.

The hair growing days were between 15 to20 days after topical application of the mentioned treatment compared with 22-25 days in control group, while the recovery days were, between 7 days to 13 days of treatment compared to 16-20 days in control.

Burn rabbit skin with acid (HCl) The skin is composed of epidermis and dermis.

The epidermis constructed of large number of polygonal layers of cells darkly stained by hematoxylin and eosin stain.

This layer of cells invaginated within the dermis forming dermal papillae which are the origin of skin derivatives, glands and / or hairs.

Numbers of hair roots were found within the loose connective tissues of the dermal structure.

Few of sweat glands were also found and some sebaceous glands were observed.

By topical spreading the concentrated HCl, the skin structure was destructed completely within some hours.

The epidermal cell die off leaving deep depression which covered by white-yellowish layer.

The sebaceous glands and hair roots were completely destructed.

Large number of inflammatory cells was found as response of burn and/or contamination.

Burn rabbit skin with fire In burn rabbit skin with acid or fire, the destruction of epidermis, dermis with the roots of hairs were shown in the 1st and 2nd weeks in all groups, but the treatment of burns with different methods (green tea, terpenes, polyphenol and antibiotic), the structure of damaged skin was recovered with the different levels in different pervious methods treatments.

Treatment application response 1–Antibiotic response The antibiotic, baneocin zinc, was the best treatment applied on the burn wound if compared with green tea crude extract, polyphenols and terpenes fractions.

However, some burn wounds were covered leaving abnormal skin appearance and no hair growth.

Also the glands looked in abnormal structure and distribution.

The inflammatory cells increased even after, burns recovery.

The newly formed epidermis was not three layers, neither dermal papillae nor horny layer were formed.

The hair grew at first around the edges of the wounds which showed certain hyperplasia.

The hair roots developed from these edges and extent underneath the newly formed skin.

2–Crude Extract Response While the antibiotic caused the quick recovery of wound, the crude extract improved the growing of newly formed skin layers.

Large number of burns wounds was looked like the normal skin with normal hair growth.

The epidermis was darkly stained which reflected the activities of these layers to give complete epidermal structure.

At the end of experiment horny layer and hairs were grown.

However, the glands were abnormally distributed and the inflammatory cells were increased within the dermis.

3-Crude Extract Fractions Response Polyphenols application gave great attention to use such fraction in certain topical treatment, burn wounds included, while response of it and it was in lower rate if compared with above mentioned treatment.

The wounds were recovered completely, giving normal epidermis, dermis, hair roots, hairs and glands.

4-Terpenes treatment Terpenes gave another way of treatment; it was good antimicrobial material as polyphenols.

They prevent microbial growing in the wounds after the first hours of application, but, the wounds recovery was in lower rate and some burns gave abnormal appearance of the newly formed skin.

Hair roots, glands and dermal papillae were rarely found in sections of terpenes-treated skin.

The results of the present study demonstrated that green tea extract increased fibroblast and endothelial cell growth.

And this could explain in part the beneficial clinical effects that have been observed.

Terpenes gave another way of treatment, it was good antimicrobial material and so did the polyphenols.

They prevent microbial growing above the wounds after the first hours of application.

However, the wounds recovery was in lower rate and some burns gave abnormal appearance of the newly formed skin.

Hair roots, glands and dermal papillae were rarely found in sections of terpenes-treated skin.

The present results indicated that the beneficial use of green tea extract and its derivatives on healing of the burn wounds was the same or near from Baneocin drug action (antibiotic).

But, the Baneocin antibiotic has numerous side effects such as, allergic reactions: reddening, dryness of skin, efflorescence and itching.

Simultaneous use of Baneocin with diuretics like etocrinic acid or furosemid can result in ototoxic and nephrotoxic effect as the international reports.

Use of Bactreocin can exponentiate the appearance of myoneural block if used on patients receiving drugs, anesthetics and muscle relaxants, so the study recommended that the using of green tea and their derivatives (polyphenols and terpenes) in treatment is the best method than antibiotics uses.

التخصصات الرئيسية

علم الحيوان

الموضوعات

• الجروح و الإصابات
• الحروق
• الشاي الأخضر

عدد الصفحات

105

قائمة المحتويات

• APA
• MLA
• AMA

لغة النص

الإنجليزية

نوع البيانات

رسائل جامعية

رقم السجل

BIM-393530