The Triterpenoid Betulin Protects against the Neuromuscular Effects of Bothrops jararacussu Snake Venom In Vivo

The potential of Brazilian native plant species used in the therapy for snakebites: A literature review

Snakebite envenoming is a potentially fatal disease categorized as a neglected public health issue for not receiving the appropriate attention from national and international health authorities. The most affected people by this problem usually live in poor rural communities, where medical resources are often sparse and, in some instances, there is even a scarcity of serum therapy. The administration of the appropriate antivenom is the only specific treatment available, however it has limited efficacy against venom-induced local effects. In this scenario, various plant species are used as local first aid for the treatment of snakebite accidents in Brazil, and some of them can effectively inhibit lethality, neurotoxicity, hemorrhage, and venom enzymes activities. This review compiles a list of plants used in the treatment of snakebites in Brazil, focusing on the native Brazilian species registered in the databases Pubmed, Scielo, Scopus and Google Scholar. All these searches were limited to peer-reviewed journals written in English, with the exception of a few articles written in Portuguese. The most cited native plant species were Casearia sylvestris Sw., Eclipta prostrata (L.) L., Mikania glomerata Spreng., Schizolobium parahyba (Vell.) S.F.Blake and Dipteryx alata Vogel, all used to decrease the severity of toxic signs, inhibit proteolytic and hemorrhagic activities, thus increasing survival time and neutralizing myotoxicity effects. Different active compounds showing important activity against the snake venoms and their toxins include flavonoids, alkaloids and tannins. Although some limitations to the experimental studies with medicinal plants were observed, including lack of comparison with control drugs and unknown active extracts compounds, species with anti-venom characteristics are effective and considered as candidates for the development of adjuvants in the treatment of snake envenomation. Further studies on the chemistry and pharmacology of traditionally used plant species will help to understand the role that snakebite herbal remedies may display in local medical health systems. It might also contribute to the development of alternative or complementary treatments to reduce the number of severe disabilities and deaths.

Neuroprotective Effects of Betulin in Pharmacological and Transgenic Caenorhabditis elegans Models of Parkinson's Disease

Parkinson’s disease (PD) is the second most common degenerative disorder of the central nervous system in the elderly. It is characterized by progressive loss of dopaminergic neurons in the substantia nigra pars compacta, as well as by motor dysfunction. Although the causes of PD are not well understood, aggregation of α-synuclein (α-syn) in neurons contributes to this disease. Current therapeutics for PD provides satisfactory symptom relief but not a cure. Treatment strategies include attempts to identify new drugs that will prevent or arrest the progressive course of PD by correcting disease-specific pathogenic process. Betulin is derived from the bark of birch trees and possesses anticancer, antimicrobial, and anti-inflammatory properties. The aim of the present study was to evaluate the potential for betulin to ameliorate PD features in Caenorhabditis elegans (C. elegans) models. We demonstrated that betulin diminished α-syn accumulation in the transgenic C. elegans model. Betulin also reduced 6-hydroxydopamine-induced dopaminergic neuron degeneration, reduced food-sensing behavioral abnormalities, and reversed life-span decreases in a pharmacological C. elegans model. Moreover, we found that the enhancement of proteasomes activity by promoting rpn1 expression and downregulation of the apoptosis pathway gene, egl-1, may be the molecular mechanism for betulin-mediated protection against PD pathology. Together, these findings support betulin as a possible treatment for PD and encourage further investigations of betulin as an antineurodegenerative agent.

Ethnobotanical study of medicinal plants used by Ribeirinhos in the North Araguaia microregion, Mato Grosso, Brazil

ETHNOPHARMACOLOGICAL IMPORTANCE

Currently, in many traditional communities, such as the riverine community in the North Araguaia microregion (Mato Grosso, Brazil), plant knowledge and use represent the main, if not the only, therapeutic resource for the maintenance of health and/or treatment of diseases. This study aimed to identify and document species of medicinal plants used by local experts from riverine communities in the North Araguaia microregion in Mato Grosso State, and to further chemical and pharmacological studies on species selected based on searches in the relevant literature.

MATERIALS AND METHODS

This is a cross-sectional ethnobotanical study, with non-probabilistic sampling (n =60), that applied the snowball method to select local riverine experts who understand medicinal plant use. Socio-demographic, ethnobotanical and ethnopharmacological data (vernacular name, uses, geographical origin, habit, method of preparation and part used) on medicinal plants were collected during semi-structured interviews. The results were analyzed by descriptive and quantitative means: indices of use-report (UR) were used to select plant species with therapeutic potential.

RESULTS

In total, 309 plant species belonging to 86 botanical families were cited; 73% were native to Brazil, and Fabaceae was the most representative family (11.3%). Arboreal was the predominant life form (37.2%). The leaf was the most used part (28.9%). Infusion was the most commonly reported method of preparation (31.3%). The plants reported in the survey were indicated for 18 of the 22 ICD-10 disease categories. The disease categories most commonly cited were the infectious and parasitic diseases (IPD, 718 UR), digestive system diseases (DSD, 565 UR) and respiratory system diseases (RSD, 504 UR), representing 16.6%, 13.1% and 11.7%, respectively of the total UR. Dysphania ambrosioides L. was the most sighted in the IPD category 50 UR. Copaifera langsdorffii Desf. (133), Lafoensia pacari A. St.-Hil. (131), and Cecropia pachystachya Trécul (126) were the species with the highest UR. Bidens pilosa L., Vernonia ferruginea Less, and L. pacari, respectively, were the most cited native plants used to treat such diseases. Of the 8 investigated native plants, C. langsdorffii, and Brosimum gaudichaudii are the most prominent: in addition to having been widely studied, in terms of phytochemical and pharmacological, these species have been marketed as pharmaceutical products, with associated patent deposits.

CONCLUSIONS

Local riverine experts from the North Araguaia microregion use a wide variety of medicinal plants in self-care health, especially those species used to treat IPD. The therapeutic potential of some of these plants has been scientifically validated; however, there are other species whose pharmacological effects and safety remain to be properly investigated. Thus, the present study, aside from being a basis for future chemical, pharmacological and agronomic bioprospecting studies, may contribute to the development of the management, conservation and sustainable use of medicinal flora in the microregion studied.

Evaluation of Betulin Mutagenicity by Salmonella/Microsome Test

Purpose: Betulin is a pentacyclic triterpene found in the outer barks of innumerous plants. This secondary metabolite is easily isolated from plants with the major interest in converting it to betulinic acid, which pharmacological properties were much more exploited than betulin. But, investments in the own betulin have been grown since no chemical step is necessary. In this study we focused the precursor betulin in order to evaluate its mutagenicity by Salmonella/microsome assay (Ames test). Methods: The Ames test was carried out using a commercial betulin exposed to Salmonella typhimurium strains TA98, TA100, TA102, and TA97a, in experiments with (+S9) and without (-S9) metabolic activation. Results: Betulin was unable to increase the number of revertants (+S9 and -S9 metabolic activation) showing the absence of any mutagenic effect by Ames test. Conclusion: This study allowed attribute safety to betulin being important for exploiting its pharmacological uses.