Effects of Aloe vera on gap junctional intercellular communication and proliferation of human diabetic and nondiabetic skin fibroblasts

Use of medicinal plants as feed additives in the diets of Mozambique tilapia (Oreochromis mossambicus) and the African Sharptooth catfish (Clarias gariepinus) in Southern Africa

Mozambique tilapia (Oreochromis mossambicus) and the African Sharptooth catfish (Clarias gariepinus) are the most farmed freshwater fish species in Southern Africa. However, production in the freshwater aquaculture sector has remained low due to, among other key factors, high cost of feeds, disease outbreaks, and poor sexual development in broodstock. Small-scale farmers are affected the most because they often lack resources and cannot afford expensive commercial diets, antimicrobials, and synthetic hormones needed to regulate reproduction. Among the proposed solutions, the inclusion of medicinal plants as feed additives is the most promising alternative to enhance growth performance, disease resistance and reproduction in fish. Plants contain various compounds such as polyphenols, carbohydrates, amino acids, flavonoids, alkaloids, tannins, organic acids, volatile oils, polysaccharides, minerals, and vitamins, some of which are necessary for growth and improving immunity or overall wellbeing in fish and other animals. However, the utilization of plants as feed additives in aquafeeds is still limited in Southern Africa. This paper reviews the potential role that medicinal plants can play as feed additives in order to promote growth performance, immunity, disease resistance, and reproduction in the culture of O. mossambicus and C. gariepinus in Southern Africa. The objective was to consolidate information about plants that can be specifically applied in freshwater aquaculture in Southern Africa by highlighting their availability and efficacy as either growth promoters or immunostimulants or fertility enhancer.

Effects of Aloe vera extract on growth, viability, ultrastructure and expression of mRNA for antioxidant enzymes in bovine secondary follicles cultured in vitro

This study aimed to investigate the effects of Aloe vera extract on follicular growth, viability, ultrastructure, and mRNA levels for superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase 1 (GPX1) and peroxiredoxin 6 (PRDX6) in bovine secondary follicles cultured in vitro. To this end, secondary follicles were mechanically isolated from the ovarian cortex and cultured at 38.5 °C, with 5% CO₂ in air, for 18 days in TCM-199⁺ alone or supplemented with 2.5%, 5.0%, 10.0% and 20.0% Aloe vera extract. Follicular growth, morphology and antrum formation were evaluated every 6 days, while ultrastructure was evaluated at the end of culture. Analysis of viability was performed by calcein-AM and ethidium homodimer-1, while mRNA levels for SOD, CAT, GPX1 and PRDX6 were evaluated by real-time PCR at the end of culture. The results show that follicles cultured with 2.5% Aloe vera had increased the rate of antrum formation, while 2.5% and 5.0% Aloe vera improved follicular viability rate. Follicles cultured with 2.5% and 10.0% Aloe vera increased the levels of mRNA for SOD and GPX1 respectively, but the levels of CAT were reduced in follicles cultured with 2.5%, 5.0%, 10.0% and 20.0%. Additionally, follicles cultured with 2.5% of Aloe vera had their ultrastructure well preserved, while those cultured with 5.0%, 10.0% and 20.0% exhibited increased oocyte vacuolization and damaged organelles. In conclusion, 2.5% Aloe vera increases antrum formation, viability and expression of mRNA for SOD in cultured secondary follicles, but higher concentrations of Aloe vera have negative effects on follicular ultrastructure.

Hormesis: wound healing and fibroblasts

Hormetic dose responses are reported here to occur commonly in the dermal wound healing process, with the particular focus on cell viability, proliferation, migration and collagen deposition of human and murine fibroblasts with in vitro studies. Hormetic responses were induced by a wide range of substances, including endogenous agents, pharmaceutical preparations, plant-derived extracts including many well-known dietary supplements, as well as physical stressor agents such as low-level laser treatments. Detailed mechanistic studies have identified common signaling pathways and their cross-pathway communications that mediate the hormetic dose responses. These findings complement and extend a similar comprehensive assessment concerning the occurrence of hormetic dose responses in keratinocytes. These findings demonstrate the generality of the hormetic dose response for key wound healing endpoints, suggesting that the hormesis concept has a fundamental role in wound healing, with respect to guiding strategies for experimental evaluation as well as therapeutic applications.

Carrier oils in dermatology

Wounds are a common medical infliction. With the increase in microbial resistance and a shift of interest towards complementary medicines, essential oils have been shown to be beneficial in suppressing microbial growth. However, in practice, essential oils are more often diluted into a base due to the risk of topical adverse effects, such as dermatitis. There is a lack of collated evidence-based information on toxicity and efficacy of carrier oils. The current information on the subject matter is restricted to generic, aroma-therapeutic books and pamphlets, based on anecdotal evidence rather than an experimental approach. Therefore, this review aimed at identifying the recommended carrier oils used in dermatology and thereafter collating the scientific evidence to support the use of carrier oils together with essential oils recommended for dermatological use. Aloe vera gel had multiple studies demonstrating the ability to enhance wound healing; however, several other carrier oils have been largely neglected. It was observed that the extracts for certain plant species had been used to justify the use of the carrier oils of the same plant species. This is an inaccurate cross assumption due to the difference in chemical composition and biological activities. Lastly, despite these carrier oils being recommended as a base for essential oils, very little data was found on the interactive profile of the carrier oil with the essential oil. This review provides a platform for further studies, especially if essential oils are to receive credence in the scientific field.

Molecular Concept of Diabetic Wound Healing: Effective Role of Herbal Remedies

The incidence of diabetes mellitus (DM) is on the rise, worldwide. One of the main complications in DM is delayed wound healing and it often requires amputation. Various drugs were used to treat DM but they presented with adverse effects. Often, patients failed to comply with such treatment. This opened the door for complementary and alternative medicine. In the present review, we explored the molecular concept of wound healing occurring in different stages with special emphasis to DM. We also highlighted the potential herbal products such as NF3 (Chinese 2-Herb Formula), Zicao, Jing Wan Hong ointment, Aleo vera, mixture of Adiantum capillus-veneris, Commiphora molmol, Aloe vera, and henna, Phenol-rich compound sweet gel, Jinchuang ointment, San-huang-sheng-fu (S) oil, Yi Bu A Jie extract, Astragali Radix (AR) and Rehmanniae Radix (RR), Yiqi Huayu, Tangzu yuyang ointment, Shengji Huayu recipe, Angelica sinensis, Lithospermun erythrorhison, Hippophae rhamnoides L., Curcuma longa and Momordica charantia that could be used effectively to treat DM wounds. Future clinical trials are needed for designing potential drugs which may be effective in treating DM wounds.

Aloe vera enhances the innate immune response of pacu (Piaractus mesopotamicus) after transport stress and combined heat killed Aeromonas hydrophila infection

In this study, pacu (Piaractus mesopotamicus) were fed with diets containing Aloe vera for 10 days prior to transport stress and infection with heat killed Aeromonas hydrophila. A. vera is popular around the world due to its medicinal properties, including immunostimulatory effects which was observed in this study. The results show that transport causes immunosuppression, an effect that was prevented by A. vera. Specifically, A. vera prevented reductions of both leukocyte respiratory burst and hemolytic activity of complement system caused by transport. Further, fish fed with A. vera also showed significantly higher leukocyte respiratory burst, serum lysozyme concentrations and activity of complement system 24 h after bacterial infection. Additionally, we observed that A. vera may modulate the innate response through activation of complement system during bacterial immune stimulation. In summary, A. vera extract enhanced innate immune parameters and consequently the ability of fish to cope with pathogens following transport stress. These findings show that A. vera has promise for use in aquaculture and add further evidence that medicinal herbs added to fish feed assist to prevent disease outbreaks.

Traditional Therapies for Skin Wound Healing

Significance: The regeneration of healthy and functional skin remains a huge challenge due to its multilayer structure and the presence of different cell types within the extracellular matrix in an organized way. Despite recent advances in wound care products, traditional therapies based on natural origin compounds, such as plant extracts, honey, and larvae, are interesting alternatives. These therapies offer new possibilities for the treatment of skin diseases, enhancing the access to the healthcare, and allowing overcoming some limitations associated to the modern products and therapies, such as the high costs, the long manufacturing times, and the increase in the bacterial resistance. This article gives a general overview about the recent advances in traditional therapies for skin wound healing, focusing on the therapeutic activity, action mechanisms, and clinical trials of the most commonly used natural compounds. New insights in the combination of traditional products with modern treatments and future challenges in the field are also highlighted. Recent Advances: Natural compounds have been used in skin wound care for many years due to their therapeutic activities, including anti-inflammatory, antimicrobial, and cell-stimulating properties. The clinical efficacy of these compounds has been investigated through in vitro and in vivo trials using both animal models and humans. Besides the important progress regarding the development of novel extraction methods, purification procedures, quality control assessment, and treatment protocols, the exact mechanisms of action, side effects, and safety of these compounds need further research. Critical Issues: The repair of skin lesions is one of the most complex biological processes in humans, occurring throughout an orchestrated cascade of overlapping biochemical and cellular events. To stimulate the regeneration process and prevent the wound to fail the healing, traditional therapies and natural products have been used with promising results. Although these products are in general less expensive than the modern treatments, they can be sensitive to the geographic location and season, and exhibit batch-to-batch variation, which can lead to unexpected allergic reactions, side effects, and contradictory clinical results. Future Directions: The scientific evidence for the use of traditional therapies in wound healing indicates beneficial effects in the treatment of different lesions. However, specific challenges remain unsolved. To extend the efficacy and the usage of natural substances in wound care, multidisciplinary efforts are necessary to prove the safety of these products, investigate their side effects, and develop standard controlled trials. The development of good manufacturing practices and regulatory legislation also assume a pivotal role in order to improve the use of traditional therapies by the clinicians and to promote their integration into the national health system. Current trends move to the development of innovative wound care treatments, combining the use of traditional healing agents and modern products/practices, such as nanofibers containing silver nanoparticles, Aloe vera loaded into alginate hydrogels, propolis into dressing films, and hydrogel sheets containing honey.

Diabetes mellitus and its management with medicinal plants: A perspective based on Iranian research

ETHNOPHARMACOLOGICAL RELEVANCE

Complementary and alternative medicine has been increasingly used to treat chronic illnesses, such as diabetes mellitus. However, various limitations in terms of their application and efficacies exist. Furthermore, there is still much to be done to discover the right herbal medicine for diabetes.

AIM OF THE STUDY

This paper aims to evaluate previous herbal studies on the management of diabetes mellitus, to address their strengths and weaknesses and propose a general framework for future studies.

APPROACH AND METHODS

Data sources such as PubMed, ScienceDirect, Scopus, SpringerLink, and Wiley were searched, limited to Iran, using 36 search terms such as herbal, traditional, medicine, and phytopharmacy in combination with diabetes and related complications. Reviewed articles were evaluated regarding the use of botanical nomenclature and included information on (1) identity of plants and plant parts used, (2) the processing procedure, and (3) the extraction process. The main outcomes were extracted and then surveyed in terms of the efficacies of herbs in the management of diabetes mellitus. Then a comparative study was performed between Iranian and non-Iranian studies with respect to herbs best studied in Iran.

RESULTS

Of the 82 herbs studied in Iran, only six herbs were endemic and 19 were studied in detail. Although most of the reviewed herbs were found to decrease the level of blood glucose (BG) and/or glycated hemoglobin (HbA1C) in both Iranian and non-Iranian studies, information on their pharmacological mechanisms is scarce. However, the level of HbA1C was measured in a limited number of clinical trials or animal studies. Available information on both short- and long-term use of studied herbs on diabetes related complications and functions of involved organs as well as comorbid depression and/or simultaneous changes in lifestyle is also insufficient. Furthermore, little or no information on their phytochemical, toxicological, and herb-drug interaction properties is available. It is worth noting that the efficacy of the reviewed herbs has been studied scarcely in both humans and animals regarding both Iranian and non-Iranian studies. A significant number of reviewed articles failed to cite the scientific name of herbs and include information on the processing procedure and the extraction process.

CONCLUSIONS

Treatment of diabetes mellitus as a multifactorial disease using herbal medicines requires a comprehensive approach. In order to discover the right herbal medicine for the management of diabetes many other important factors than the levels of BG, HbA1C and insulin should be considered. According to our criteria, all the reviewed herbs suffered from inadequate investigation in human, animal and in vitro models in this respect, whereas they are worth investigating further. However, more research on endemic plants and the traditional history of herbal medicine is warranted. In our opinion, the pharmacological, toxicological, and phytochemical information should be obtained before clinical trials. Furthermore, information such as botanical scientific nomenclature, side effects, and toxicity will improve the quality and validity of publications in herbal research. In particular, designing a database covering all valid information about herbs and/or diseases will decrease unnecessary costs and increase the efficiency of research.

Aloe vera: an in vitro study of effects on corneal wound closure and collagenase activity

PURPOSE

To evaluate the in vitro effects of an aloe vera solution on (i) the viability and wound healing response of corneal cells and (ii) the ability to alter collagenase and gelatinase activities.

METHODS

Primary cultures of corneal epithelial cells and fibroblasts were prepared from grossly normal enucleated canine globes and treated with an aloe solution (doses ranging from 0.0-2 mg/mL). Cellular viability was evaluated using a colorimetric assay. A corneal wound healing model was used to quantify cellular ingrowth across a defect made on the confluent surface. Anticollagenase and antigelatinase activities were evaluated by incubating a bacterial collagenase/gelatinase with aloe solution (doses ranging from 0.0-500 μg/mL) and comparing outcome measures to a general metalloproteinase inhibitor, 1, 10-phenanthroline, and canine serum (doses ranging from 0.0-100%).

RESULTS

None of the concentrations of aloe solution tested significantly affected the viability of corneal epithelial cells or fibroblasts. Concentrations ≤175 μg/mL slightly accelerated corneal epithelial cell wound closure; this change was not significant. Concentrations ≥175 μg/mL significantly (P ≤ 0.001) slowed the rate of corneal fibroblast wound closure, while aloe concentrations <175 μg/mL did not significantly alter fibroblast wound closure. Aloe solution did not alter the ability for collagenase to degrade gelatin or collagen Type I but increased the ability for collagenase to degrade Type IV collagen.

CONCLUSIONS

Although additional experiments are required, lower concentrations of aloe solution may be beneficial in healing of superficial corneal wounds to help decrease fibrosis and speed epithelialization. An increase in collagenase activity with aloe vera warrants further testing before considering in vivo studies.

Ethnodiagnostic skills of the digo community for malaria: a lead to traditional bioprospecting

Malaria is a major public health problem that is presently complicated by the development of resistance by Plasmodium falciparum to the mainstay drugs. Thus, new drugs with unique structures and mechanism of action are required to treat drug-resistant strains of malaria. Historically, compounds containing a novel structure from natural origin represent a major source for the discovery and development of new drugs for several diseases. This paper presents ethnophytotherapeutic remedies, ethnodiagnostic skills, and related traditional knowledge utilized by the Digo community of the Kenyan Coast to diagnose malaria as a lead to traditional bioprospecting. The current study was carried out in three Digo villages of Diani sub-location between May 2009 and December 2009. Data was collected using semi-structured interviews, and open and close-ended questionnaires. A total of 60 respondents (34 men and 26 women) provided the targeted information. The results show that the indigenous knowledge of Digo community on malaria encompasses not only the symptoms of malaria but also the factors that are responsible for causing malaria, attributes favoring the breeding of mosquitoes and practices employed to guard against mosquito bites or to protect households against malaria. This knowledge is closely in harmony with scientific approaches to the treatment and control of the disease. The Digo community uses 60 medicinal plants distributed in 52 genera and 27 families to treat malaria. The most frequently mentioned symptoms were fever, joint pains, and vomiting while the most frequently mentioned practices employed to guard against mosquito bites and/or to protect households against malaria was burning of herbal plants such as Ocimum suave and ingestion of herbal decoctions and concoctions. The Digo community has abundant ethnodiagnostic skills for malaria which forms the basis of their traditional bioprospecting techniques.

The effect of aloe vera oral administration on cutaneous wound healing in type 2 diabetic rats

Delayed wound healing is one of the complications of diabetes mellitus. The present study was performed to investigate the effect of Aloe vera oral administration on open wounds in type 2 diabetic rats. Full thickness open wounds (1.5 × 1.5 cm) were created under general anesthesia on the backs of the rats. These rats were divided into two group, a control group (Group C) and an Aloe vera oral administration group (Group A). Each wound area was measured on days 1, 2, 4 and 8 postwounding. The stages of wound granulation tissues were evaluated histopathologically. The expression of transforming growth factor (TGF)-β1 and vascular endothelial growth factor (VEGF) were determined by immunohistochemically. The wounds were significantly contracted in Group A on days 2, 4 and 8 postwounding. Histological results revealed that the inflammatory cell infiltration, angiogenesis, extracellular matrix deposition and epithelialization were promoted in Group A, respectively. The immunohistochemical results revealed that both TGF-β1 and VEGF protein-positive cells increased in Group A on day 4 postwounding. We concluded that Aloe vera oral administration accelerated wound healing in type 2 diabetic rats.

Plants used for the treatment of diabetes in Jordan: a review of scientific evidence

CONTEXT

Diabetes is a serious disease which has reached epidemic proportions in many parts of the world. Despite the tremendous developments in medicinal chemistry, traditional medicine is still a common practice for the treatment of diabetes.

OBJECTIVES

In Jordanian traditional medicine, 69 plant species are used by diabetic patients to reduce glucose levels in blood. The aim of the present study is to report these plants and link their traditional use with scientific evidence confirming their claimed activity. The plant part(s) used, method(s) of preparation, common Arabic names, and other ethnopharmacological uses are also listed.

MATERIALS AND METHODS

The literature and databases (SciFinder, PubMed, ScienceDirect and Scirus) have been thoroughly investigated and the plants used have been grouped according to the reported scientific evidence.

RESULTS

Results showed that 40 plants have been reported to possess hypoglycemic activities in in vivo/in vitro experiments. Five plant species did not exhibit in vivo hypoglycemic activity, while 24 plants had not been studied for such an activity. Twenty plants had been screened for their α-amylase/α-glucosidase inhibitory activities.

DISCUSSION

The reported in vivo and in vitro hypoglycemic as well as α-amylase/α-glucosidase inhibitory activities of these plants are discussed.

CONCLUSION

Additional in vitro and in vivo studies are needed to test the hypoglycemic activity of the plants with claimed antidiabetic activity which has not yet been evaluated. Identification of the active ingredients of potent plants might generate lead compounds in drug discovery and development.

Acemannan stimulates gingival fibroblast proliferation; expressions of keratinocyte growth factor-1, vascular endothelial growth factor, and type I collagen; and wound healing

Aloe vera has long been used as a traditional medicine for inducing wound healing. Gingival fibroblasts (GFs) play an important role in oral wound healing. In this study, we investigated the effects of acemannan, a polysaccharide extracted from Aloe vera gel, on GF proliferation; keratinocyte growth factor-1 (KGF-1), vascular endothelial growth factor (VEGF), and type I collagen production; and oral wound healing in rats. [(3)H]-Thymidine incorporation assay and ELISA were used. Punch biopsy wounds were created at the hard palate of male Sprague Dawley rats. All treatments (normal saline; 0.1% triamcinolone acetonide; plain 1% Carbopol; and Carbopol containing 0.5%, 1%, and 2% acemannan (w/w)) were applied daily. Wounded areas and histological features were observed at day 7 after treatment. From our studies, acemannan at concentrations of 2, 4, 8, and 16 mg/ml significantly induced cell proliferation (P<0.05). Acemannan concentrations between 2 - 16 mg/ml significantly stimulated KGF-1, VEGF, and type I collagen expressions (P<0.05). Wound healing of animals receiving Carbopol containing 0.5% acemannan (w/w) was significantly better than that of the other groups (P<0.05). These findings suggest that acemannan plays a significant role in the oral wound healing process via the induction of fibroblast proliferation and stimulation of KGF-1, VEGF, and type I collagen expressions.

Effects of Danshen and Total Saponins of Panax Notoginsen on rat hepatocarcinoma cells and bystander effect of suicide gene

AIM: To explore the effects of Danshen and Total Saponins of Panax Notoginsen (PNS) on rat hepatoca-rcinoma cells and the bystander effect of herpes simpl-ex virus thymidine kinase gene/ganciclovir (HSV-tk/GCV).

METHODS: Rat hepatocarcinoma cell line CBRH7919 (tk-), CBRH7919 (tk+) and the 5-10% tk+ mixed cells were treated with diverse concentrations of Danshen injection, PNS, GCV separately, or Danshen injection plus GCV and PNS plus GCV (n = 3, 6). The survival rate of the cells in each group was examined by MTT method, and q-value analysis was used to estimate the synergistic effect of traditional Chinese medicine on the suicide gene system. The q-value was equal to the ratio of the actual effect of combined treatment to its theoretical effect. The effect was classified into three categories: antagonistic effect (q ≤0.85), additive effect (0.85 ≤ q <1.15), and synergistic effect (q ≥1.15).

RESULTS: After the treatment of 5, 10, 20, 40 mL/L Danshen injection for 72 h, the survival rate of CBRH 7919 (tk-) was 81.0±17.3%, 55.6±12.0%, 14.6±4.4%, and 11.5±0.9%, respectively. IC₅₀ was 11.4 mL/L. The survival rate of the hepatocarcinoma cells was 78.9±27.9% in the 5% tk+/GCV group, and 84.3±18.2% in the GCV group, and the survival rate in the former was 7.6% lower than that in the latter. The survival rate of the cells was 47.8±16.5% (q = 1.60) in the group of 5 mL/L Danshen injection combined with 5% tk+/GCV, and 72.8±4.5% in the group of 5 mL/L Danshen injection combined with GCV, and the survival rate in the former was 34.3% lower than that in the latter. The survival rate was 12.2±5.9% (q = 1.46) in the group of 10 mL/L Danshen injection combined with 5% tk+/GCV, and 36.5±2.7% in the group of 10 mL/L Danshen injection combined with GCV, and the survival rate in the former was 66.3% lower than that in the latter. The survival rate of CBRH7919 (tk-) was 104.1±3.7%, 107.6±3.1%, 69.7±8.5%, and 59.3±2.9%, respectively, after the treatment of 10, 50, 100, and 140 mg/L PNS for 72 h. IC₅₀ was 220 mg/L. The survival rate in the 10% tk+/GCV group was 17.2% (P <0.05) lower than that in the GCV group. In the group of 50 mg/L and 100 mg/L PNS combined with 10% tk+/GCV (q = 0.89, 0.87), the survival rates were 17.7% and 18.3% lower than those in the corr-esponding groups of PNS combined with GCV, respec-tively.

CONCLUSION: Danshen injection can inhibit the prolif-eration of hepatocarcinoma cells significantly, and can synergically enhance the killing and bystander effect of tk/GCV system. PNS can also inhibit the proliferation of hepatocarcinoma cells to some extent, but it has only additive effect on the tk/GCV system, while no synerg-etic effect.

Phytotherapy: an alternative treatment for non-healing ulcers

There are few reports in the literature on the effectiveness of complimentary therapies on chronic wounds. Use of an aloe vera gel resulted in full healing after treatments such as antibiotics, surgical debridement and skin grafting had failed.