PHARMACEUTICAL COMPOSITIONS FOR THE TOPICAL USE CONTAINING MEDICINAL PLANTS EXTRACTS WITH ANTIPHLOGISTIC AND CICATRISING ACTIVITIES
The present invention relates to pharmaceutical compositions for the topical use containing extracts of chamomile heads (Matricaria recutita), althaea roots (Althaea officinalis L.), malva flowers (Malva sylvestris), large- leaved lime flowers (Tillia Platyphyllos) and milfoil flowers (Achillea millefolium L.), endowed with anti-inflammatory and cicatrising properties, for the treatment of skin inflammations and lesions. INTRODUCTION
The formation of bedsores, i.e. skin lesions which, due to reduced tissutal perfusion and loss of skin trophism and elasticity, tend to become chronic, is one of the most widespread consequences of protracted infirmity, especially in the elderly.
The most severe cases can be nowadays treated by means of skin and keratinocytes transplants.
Nevertheless, novel remedies for preventing or healing the lesions at the beginning or at the first evolution steps would be valuable in that they would limit recourse to surgery. Several products for the topical use presently available on the market contain non steroidal or steroidal anti-inflammatory drugs and their prolonged use favours side-effects onset. Therefore, it would be useful to provide for products that contain active natural principles endowed with anti-inflammatory and cicatrising properties. Research for new compounds for the treatment of the above mentioned lesions has focused for some time on natural substances, which are usually better tolerable and lack side effects.
Attention has been centered in particular on chamomile, due to its
antiinflammatory and antimicrobial properties. Said properties, particularly in case of topical use, are apparently ascribable only in negligible extent to the essential oil components (camazulene, α-bisabolol, matricine, etc.) and rather to the hydrosoluble components, i.e. flavonoids (apigenin, luteolin, quercitine, ratine and glucoside derivatives). It is assumed that flavonoids act by preventing histamine effects and oxygen free radicals release rather than by inhibiting arachidonic acid pathway. This mechanism could explain not only chamomile antiphlogistic activity, but also its cicatrising effect. In fact, the accumulation of free radicals reduces the tensile strength of the lesions by inhibiting hyaluronic acid, thus preventing tissutal reparative processes. Healing of skin lesions apparently occurs through a first "inflammatory" phase followed by a neo-angiogenesis and granulation tissue formation phase, with wound contraction and subsequent cicatrization and re-epithelization.
It has now been found that chamomile anti-inflammatory and cicatrising properties are enhanced upon combination with other vegetable components, such as milfoil, malva, large-leaved lime flowers and althaea roots. DISCLOSURE OF THE INVENTION
Object of the present invention are pharmaceutical compositions for topical use containing extracts of chamomile heads (Matricaria recutitά), althaea roots (Althaea officinalis L.), malva flowers (Malva sylvestris), large-leaved lime flowers (Tillia Platyphyllos) and milfoil flowers (Achillea millefolium L.), useful for the treatment of skin infiammations and lesions.
Said pharmaceutical compositions are preferably in the form of creams, gels, pastes or ointments, in which the extracts total content ranges from 10 to 40%.
A preferred embodiment of the invention consists in a cream containing 20% extracts in Essex® base cream (hereinafter referred to as BAR 2).
The compositions can be prepared from extracts of each vegetable component, or from an extract obtainable from a mixture of all the vegetable components.
Moreover, it is an object of the present invention a process for the preparation of an extract of chamomile heads (Matricaria recutita), althaea roots
(Althaea officinalis L.), malva flowers (Malva sylvestris), large-leaved lime flowers (Tillia Platyphyllos) and milfoil flowers (Achillea millefolium L.) comprising soaking a mixture of the vegetable components, preferably in equal amounts, in an extraction mixture consisting of distilled water and ethyl alcohol. The vegetable components/extraction mixture ratio ranges from 1:8 to 1 : 12 w/v, whereas the distilled water/ethyl alcohol ratio ranges from 10:90 to 50:50 v/v, preferably 30:70 v/v. After soaking for 22 - 26 hours, preferably 24 hours, the liquid phase is recovered by filtration, preferably under vacuum, and evaporated under reduced pressure at a temperature not higher than 35°C. According to a preferred embodiment of the invention, 100 g vegetable components mixture is soaked in a 30/70 v/v distilled water/ethanol mixture, up to 1 litre final volume.
After 24 hours the liquid phase is recovered by filtration under vacuum and evaporated under reduced pressure. The resulting extract is hereinafter referred to as BAR 1. The anti-inflammatory and cicatrising properties of the compositions containing the extracts of the invention were evaluated in rats by means of the following tests:
Carrageenin oedema test (table 1) Dextran oedema test (table 2) - Skin excoriations test (table 3)
Skin ulcers test (table 4) The antiphlogistic effect was evidenced in tests using the extract BAR 1, whereas the cicatrising effect was evidenced in tests using the cream BAR
2, because it adheres better to the treated skin and allows more thorough inspection, due to its more transparent colour than BAR l 's.
Both the extract and the cream showed active, in fact topical application on rat skin reduced in a statistically significant way inflammation and oedema in the carrageenin and dextran oedema tests and enhanced the cicatrising action in the experimental excoriations and ulcers tests.
It is therefore a further object of the present invention the use of the extract obtainable according to the above described process for the preparation of medicaments for the topical use, in particular for the treatment of skin inflammations and/or lesions.
The invention is hereinafter illustrated in more detail by the following examples.
EXAMPLES
Example 1; Preparation of BAR 1 extract BAR 1 extract was prepared soaking for 24 hours a mixture consisting of 100 g of each vegetable component, suitably ground, in distilled water and ethyl alcohol (30:70 v/v), to a final volume of one litre, stored in a tightly sealed dark vessel.
After soaking, the liquid phase was recovered by filtration under vacuum and the intense green liquid was evaporated under reduced pressure at a temperature of 30-35°C, to avoid degradation.
Example 2: Preparation of Cream BAR 2
Cream BAR 2 was prepared incorporating 20 g of BAR 1 extract in
80 g of Essex® base cream. Example 3: Pharmacological tests
Animals
The experiments hereinafter described were carried out on male
Sprague-Dawley rats, (about 120-150 g weight) purchased from Harlan Italy (Udine, Italy), housed in single cages, under controlled temperature and humidity (22±1°C, 60% humidity).
Treatments BAR 1 extract or Cream BAR 2 were applied on the area to be treated.
Carrageenin oedema test
A suspension of carrageenin (0.1 ml, 1% in normal saline) was administered to one of the rats hind paws.
The leg volume was evaluated with a pletismometer (Basile, Varese), prior to carrageenin injection (reference value) and after 2, 4, 8, 24 hours. The values reported in the table refer to percentage increases in the paw volume compared with the reference value. BAR 1 extract was applied to the rat paw immediately after carrageenin injection and after each evaluation. Dextran oedema test
A 5% dextran solution (0.1 ml) in saline was administered to one of the rats hind paws.
The leg volume was evaluated with a pletismometer (Basile, Varese), prior to dextran injection (reference value) and after 2, 4, 8, 24 hours. The values reported in the table refer to percentage increases in the leg volume compared with the reference value. BAR 1 extract was applied to the rat paw immediately after carrageenin injection and after each evaluation.
Skin excoriations test
Animals were anaesthetised with Ketavet (Gellini pharmaceutical), then shaved on the back so as to define a 1.5 cm diameter circular area. After that, the skin was scarified with a scalpel, then Essex® base cream was applied to control animals, whereas BAR 2 was applied to the treated ones.
Applications were repeated twice a day for 5 days. The cicatrising activity of
BAR 2 was evaluated at 48, 72 and 96 hours from excoriations, using an arbitrary numerical scale (from 0 to 4), according to what described in Tamburini M. et al (Acta Phytoter. 3: 116-121 :2000).
Skin ulcers test Animals were anaesthetised with Ketavet (Gellini pharmaceutical), and shaved on the back, then an incision of 1.5 cm length was performed. Essex® base cream was applied to controls, whereas BAR 2 was applied to treated animals. Applications were repeated twice a day for 5 days. The reparative cicatrising activity of BAR 2 was evaluated at 48, 72 and 96 hours from incision, using an arbitrary numerical scale (from 0 to 4), according to what described in Tamburini M. et al (Acta Phytoter. 3: 116-121 :2000).
Results
Anti-inflammatory activity
Table 1 shows that in a 24 hours evaluation BAR 1 reduces carrageenin-induced oedema in a statistically significant way compared with controls, at any surveying time.
Moreover, BAR 1 significantly reduces (table 2) the percentage of paw volume increase induced by dextran, and is particularly active between 4-6 hours. Table N°l: Effect induced by BAR 1 on carrageenin oedema in rats
Statistical analysis : Student's T
Table N° 2: Effect induced by BAR 1 on dextran oedema in rats
Statistical analysis: Student's T Cicatrising activity Table 3 shows that BAR 2 accelerates cutaneous reparative processes subsequent to excoriations. Values observed at 48, 72 and 96 hours from excoriations are in fact much higher in treated animals than in controls. In particular, the effect is statistically significant at 72 and 96 hours.
Moreover, the cream accelerates ulcers cicatrisation (table 4) in a statistically significant way between 72 and 96 hours compared with controls. Table N° 3: Effects of Cream BAR 2 in the skin excoriations test
The reported results refer to average scores obtained using an arbitrary scale (from 0 to 4, wherein 4 means complete cicatrization). Statistical analysis: Student's T
Table N° 4: Effects of Cream BAR 2 in the experimental skin ulcers test
The reported results refer to average scores obtained using an arbitrary scale (from 0 to 4, wherein 4 means complete cicatrization). Statistical analysis: T di Student
Conclusions
The results show that BAR 1 extract and the topical pharmaceutical compositions containing it have excellent antiphlogistic and cicatrising activities. Therefore, the pharmaceutical compositions containing the extracts of the invention, in particular BAR 1 extract, can be used in the treatment of skin conditions wherein reduction of inflammation and improvement of tissue repair processes are required, in particular for healing bedsores.