Tabebuia aurea decreases hyperalgesia and neuronal injury induced by snake venom

Identification of purinergic system components in the venom of Bothrops mattogrossensis and the inhibitory effect of specioside extracted from Tabebuia aurea

Snake bites are a severe problem in the countryside of Brazil and are usually attributed to snakes of the genera Bothrops, Crotalus, and Lachesis. Snake venom can release ectoenzymes and nucleotidases that modulate the purinergic system. In addition to serum therapy against snake poisoning, medicinal plants with anti-inflammatory activities, such as Tabebuia aurea, is empirically applied in accidents that occur in difficult-to-access areas. This study aimed was to verify the presence and activity of nucleotidases in the crude venom of Bothrops mattogrossensis (BmtV) in vitro and characterize the modulation of purinergic components, myeloid differentiation, and inflammatory/oxidative stress markers by BmtV in vivo and in vitro. Moreover, our study assessed the inhibitory activities of specioside, an iridoid isolated from Tabebuia aurea, against the effects of BmtV. Proteomic analysis of venom content and nucleotidase activity confirm the presence of ectonucleotidase-like enzymes in BmtV. In in vivo experiments, BmtV altered purinergic component expression (P2X7 receptor, CD39 and CD73), increased neutrophil numbers in peripheral blood, and elevated oxidative stress/inflammatory parameters such as lipid peroxidation and myeloperoxidase activity. BmtV also decreased viability and increased spreading index and phagocytic activity on macrophages. Specioside inhibited nucleotidase activity, restored neutrophil numbers, and mediate the oxidative/inflammatory effects produced by BmtV. We highlight the effects produced by BmtV in purinergic system components, myeloid differentiation, and inflammatory/oxidative stress parameters, while specioside reduced the main BmtV-dependent effects.

Lapagyl mitigates UV-induced inflammation and immunosuppression via Foxp3+ Tregs and CCL pathway: A single-cell transcriptomics study

BACKGROUND

As the largest organ of the body, the skin is constantly subjected to ultraviolet radiation (UVR), leading to inflammations and changes that mirror those seen in chronological aging. Although various small molecule drugs have been explored for treating skin photoaging, they typically suffer from low stability and a high incidence of adverse reactions. Consequently, the continued investigation of photoaging treatments, particularly those utilizing herbal products, remains a critical clinical endeavor. One such herbal product, Lapagyl, is derived from the bark of the lapacho tree and possesses antioxidant efficacies that could be beneficial in combating skin photoaging.

PURPOSE

This research aimed to evaluate the efficacy of the herbal product Lapagyl in combating UVR-induced skin photoaging. Additionally, it sought to unravel the mechanisms by which Lapagyl promotes the regeneration of the skin extracellular matrix.

METHODS

To investigate whether Lapagyl can alleviate skin aging and damage, a UVR radiation model was established using SKH-1 hairless mice. The dorsal skins of these mice were evaluated for wrinkle formation, texture, moisture, transepidermal water loss (TEWL), and elasticity. Pathological assessments were conducted to determine Lapagyl's efficacy. Additionally, single-cell sequencing and spectrum analysis were employed to elucidate the working mechanisms and primary components of Lapagyl in addressing UVR-induced skin aging and injury.

RESULTS

Lapagyl markedly reduced UVR-induced wrinkles, moisture loss, and elasticity decrease in SKH-1 mice. Single-cell sequencing demonstrated that Lapagyl corrected the imbalance in cell proportions caused by UVR, decreased UVR-induced ROS expression, and protected basal and spinous cells from skin damage. Additionally, Lapagyl effectively prevented the entry of inflammatory cells into the skin by reducing CCL8 expression and curtailed the UVR-induced formation of Foxp3+ regulatory T cells (Tregs) in the skin. Both pathological assessments and ex vivo skin model results demonstrated that Lapagyl effectively reduced UVR-induced damage to collagen and elastin. Spectrum analysis identified Salidroside as the primary compound remaining in the skin following Lapagyl treatment. Taken together, our study elucidated the skin protection mechanism of the herbal product Lapagyl against UVR damage at the cellular level, revealing its immunomodulatory effects, with salidroside identified as the primary active compound for skin.

CONCLUSION

Our study provided a thorough evaluation of Lapagyl's protective effects on skin against UVR damage, delving into the mechanisms at the cellular level. We discovered that Lapagyl mitigates skin inflammation and immunosuppression by regulating Foxp3+ Tregs and the CCL pathway. These insights indicate that Lapagyl has potential as a novel therapeutic option for addressing skin photoaging.

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.

Pain modulated by Bothrops snake venoms: Mechanisms of nociceptive signaling and therapeutic perspectives

Snake venoms are substances mostly composed by proteins and peptides with high biological activity. Local and systemic effects culminate in clinical manifestations induced by these substances. Pain is the most uncomfortable condition, but it has not been well investigated. This review discusses Bothrops snakebite-induced nociception, highlighting molecules involved in the mediation of this process and perspectives in treatment of pain induced by Bothrops snake venoms (B. alternatus, B. asper, B. atrox, B. insularis, B. jararaca, B. pirajai, B. jararacussu, B. lanceolatus, B. leucurus, B. mattogrossensis, B. moojeni). We highlight, the understanding of the nociceptive signaling, especially in snakebite, enables more efficient treatment approaches. Finally, future perspectives for pain treatment concerning snakebite patients are discussed.

New derivatives of the iridoid specioside from fungal biotransformation

Iridoids are widely found from species of Bignoniaceae family and exhibit several biological activities, such as anti-inflammatory, antimicrobial, antioxidant, and antitumor. Specioside is an iridoid found from Tabebuia species, mainly in Tabebuia aurea. Thus, here fungus-mediated biotransformation of the iridoid specioside was investigated by seven fungi. The fungus-mediated biotransformation reactions resulted in a total of nineteen different analogs by fungus Aspergillus niger, Aspergillus flavus, Aspergillus japonicus, Aspergillus terreus, Aspergillus niveus, Penicillium crustosum, and Thermoascus aurantiacus. Non-glycosylated specioside was the main metabolite observed. The other analogs were yielded from ester hydrolysis, hydroxylation, methylation, and hydrogenation reactions. The non-glycosylated specioside and coumaric acid were yielded by all fungi-mediated biotransformation. Thus, fungus applied in this study showed the ability to perform hydroxylation and glycosidic, as well as ester hydrolysis reactions from glycosylated iridoid. KEY POINTS: • The biotransformation of specioside by seven fungi yielded nineteen analogs. • The non-glycosylated specioside was the main analog obtained. • Ester hydrolysis, hydroxylation, methylation, and hydrogenation reactions were observe.

Tabebuia impetiginosa: A Comprehensive Review on Traditional Uses, Phytochemistry, and Immunopharmacological Properties

Tabebuia impetiginosa, a plant native to the Amazon rainforest and other parts of Latin America, is traditionally used for treating fever, malaria, bacterial and fungal infections, and skin diseases. Additionally, several categories of phytochemicals and extracts isolated from T. impetiginosa have been studied via various models and displayed pharmacological activities. This review aims to uncover and summarize the research concerning T. impetiginosa, particularly its traditional uses, phytochemistry, and immunopharmacological activity, as well as to provide guidance for future research. A comprehensive search of the published literature was conducted to locate original publications pertaining to T. impetiginosa up to June 2020. The main inquiry used the following keywords in various combinations in titles and abstracts: T. impetiginosa, Taheebo, traditional uses, phytochemistry, immunopharmacological, anti-inflammatory activity. Immunopharmacological activity described in this paper includes its anti-inflammatory, anti-allergic, anti-autoimmune, and anti-cancer properties. Particularly, T. impetiginosa has a strong effect on anti-inflammatory activity. This paper also describes the target pathway underlying how T. impetiginosa inhibits the inflammatory response. The need for further investigation to identify other pharmacological activities as well as the exact target proteins of T. impetiginosa was also highlighted. T. impetiginosa may provide a new strategy for prevention and treatment of many immunological disorders that foster extensive research to identify potential anti-inflammatory and immunomodulatory compounds and fractions as well as to explore the underlying mechanisms of this herb. Further scientific evidence is required for clinical trials on its immunopharmacological effects and safety.

Edema, hyperalgesia and myonecrosis induced by Brazilian bothropic venoms: overview of the last decade

Snakebite accidents are considered serious public health problems. They are often neglected, and individuals who have received insufficient treatment are subjected to various disabling alterations. Snake venoms are secretions composed of biologically active molecules capable of triggering local and systemic effects in envenomation victims. Bothropic snakes are responsible for most of the ophidian accidents in Brazil; their venoms are mainly related to local manifestations, due to a composition that is especially rich in proteases and phospholipases A₂. The most common local damages are inflammation, with consequent cellular activation and release of inflammatory mediators, hemorrhage, edema, pain and (myo)necrosis, which may lead to amputation of the affected areas. Antivenom therapy is the main treatment for snakebites. However, the efficiency is mainly due to the neutralization of the toxins responsible for the systemic alterations. Thus, the local damages can evolve to markedly compromise the tissue. The complexity of these local effects associated with the toxicity of the snake venom components of the genus Bothrops, arouse interest in the study of the biochemical and pathophysiological mechanisms involved with the actions caused by toxins of the venom. Therefore, this review aims to analyze the edematogenic, hyperalgesic and myotoxic effects caused by Brazilian bothropic venoms in order to contribute to the study and elucidation of the mechanisms of action of its components and, consequently, enable discoveries of more effective combined therapies in the treatment of local damages resulting from envenoming.

In-vitro Bactericidal Activity of a Novel Plant Source Plumeria pudica against Some Human and Fish Pathogenic Bacteria

BACKGROUND

The only remedy for up surging problem of antibiotic resistance is the discovery of antibacterial agents of natural origin.

OBJECTIVE

The present study was aimed at finding antibacterial potential of crude and solvent extracts of mature leaves of Plumeria pudica.

METHODS

Antibacterial activity of three different solvent extracts were evaluated in four human and four fish pathogenic bacteria by measuring the zone of inhibition and determining Minimum Inhibitory Concentration and Minimum Bactericidal Concentration values. Standard antibiotics were used as positive control. Preliminary phytochemical screening of most effective extract i.e., ethyl acetate extract, Fourier Transform Infra Red analysis and GC-MS analysis of the Thin Layer Chromatographic (TLC) fraction of ethyl acetate extract were done meticulously. All experiments were done thrice and analyzed statistically.

RESULTS

Crude leaf extracts and solvent extracts caused good inhibition of bacterial growth in all selected bacteria. Ethyl acetate extract showed highest inhibition zones in all tested strains with maximum inhibition (19.50±0.29 mm) in Escherichia coli (MTCC 739). MBC/MIC of the extracts indicated that all three solvent extracts were bactericidal. Preliminary phytochemical tests revealed the presence of tannins, steroids and alkaloids and FT-IR analysis revealed presence of many functional groups namely alcoholic, amide, amine salt and aldehyde groups. From the GC-MS analysis of TLC fraction of ethyl acetate extract, five different bioactive compounds e.g., 2,4-ditert -butylphenyl 5-hydroxypentanoate, Oxalic acid; allyl nonyl ester, 7,9-Ditert-butyl-1-oxaspiro(4,5)deca-6,9-diene- 2,8-dione, Dibutyl phthalate and 2,3,5,8-tetramethyl-decane were identified.

CONCLUSION

Leaf extracts of P. pudica contain bioactive compounds that can be used as broad spectrum bactericidal agent.