Chronic administration of antioxidant resin from Virola oleifera attenuates atherogenesis in LDLr -/- mice

Development and Evaluation of Virola oleifera Formulation for Cutaneous Wound Healing

In regions adjacent to the Brazilian Atlantic Forest, Virola oleifera (VO) resin extract has been popularly used for decades as a skin and mucosal healing agent. However, this antioxidant-rich resin has not yet been investigated in wound healing, whose physiological process might also be aggravated by oxidative stress-related diseases (e.g., hypertension/diabetes). Our aim, therefore, was to investigate whether VO resin presents healing effects through an innovative cream for topical applications. For this, adult male Wistar rats were divided into four groups. Then, four 15 mm excisions were performed on the shaved skin. All treatments were applied topically to the wound area daily. At the end of experiments (0, 3rd, and 10th days) macroscopic analysis of wound tissue contraction and histological analysis of inflammatory cell parameters were performed. The group treated with VO cream showed the best wound contraction (15%, p < 0.05) and reduced levels of lipid peroxidation and protein oxidation (118% and 110%, p < 0.05, respectively) compared to the control group. Our results demonstrated the healing capacity of a new formulation prepared with VO, which could be, at least in part, justified by antioxidant mechanisms that contribute to re-epithelialization, becoming a promising dermo-cosmetic for the treatment of wound healing.

Evaluation of Virola oleifera activity in musculoskeletal pathologies: Inhibition of human multiple myeloma cells proliferation and combination therapy with dexamethasone or bortezomib

ETHNOPHARMACOLOGICAL RELEVANCE

Virola oleifera (Schott) A.C. Smith, Myristicaceae, has been widely used in traditional medicine in Brazil to treat rheumatic pain, joint tumours, skin diseases, halitosis, bronchial asthma, haemorrhoids, and intestinal worms. Recently, research data showed the antioxidant properties in several oxidative stress-related models. However, there is no experimental evidence supporting its potential use in managing rheumatic diseases and bone malignancies.

AIMS OF THE STUDY

To evaluate the therapeutic potential of the resin from Virola oleifera in joint and bone diseases, namely arthritis, osteosarcoma, chondrosarcoma, and multiple myeloma.

MATERIALS AND METHODS

To determine Virola oleifera resin (VO) effects on arthritis-associated inflammation and cartilage degradation, the LPS-induced NO production, and mRNA and protein expression of ADAMTS5, MMP13, COL2, and ACAN, were evaluated in chondrocytes (ATDC5 and TC28 cell lines). The cytotoxic effects of VO (0.05-50 μg/ml) on multiple myeloma (ARH-77), osteosarcoma (SAOS-2), and chondrosarcoma (SW-1353) cell lines were analysed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The VO effects, combined with dexamethasone or bortezomib, were evaluated in a multiple myeloma cell line. The mechanisms of VO, alone or in combination with bortezomib, were determined by cell cycle analysis through flow cytometry, while expression levels of p-Akt/Akt, p-ERK/ERK, p-p38/p38 MAPK, Bax, Bcl-2, and cleaved-caspase-3/caspase-3 proteins by Western blot.

RESULTS

VO had no significant effect on LPS-induced NO production in chondrocytes at non-cytotoxic concentrations. VO treatment diminished the mRNA levels of metalloproteinases and ECM components; however, any significant effect was observed on the protein expression levels. The cell viability of a multiple myeloma cell line was strongly reduced by VO treatment in a dose- and time-dependent manner, while osteosarcoma and chondrosarcoma cell lines viability was significantly affected only by the highest dose assessed. In multiple myeloma cells, VO leads to G2/M cell cycle arrest. Furthermore, it synergizes with dexamethasone by increasing cell toxicity. Finally, VO reverts bortezomib activity by counteracting ERK1/2, Bax, and caspase-3 activation.

CONCLUSIONS

The current work supports the ethnopharmacological use of Virola oleifera (Schott) A.C. Smith in bone and joint diseases, but there is no evidence for the amelioration of arthritis-associated inflammatory or catabolic processes. Our data also supports the potential use of Virola oleifera as adjuvant therapy to optimize the pharmacologic effects of current chemotherapeutic drugs. However, possible herb-drug interactions should be considered before clinical application.

Pharmacological Extracts and Molecules from Virola Species: Traditional Uses, Phytochemistry, and Biological Activity

Virola is the largest genus of Myristicaceae in America, comprising about 60 species of medium-sized trees geographically spread from Mexico to southern Brazil. The plant species of this genus have been widely used in folk medicine for the treatment of several ailments, such as rheumatic pain, bronchial asthma, tumors in the joints, intestinal worms, halitosis, ulcers, and multiple infections, due to their pharmacological activity. This review presents an updated and comprehensive summary of Virola species, particularly their ethnomedicinal uses, phytochemistry, and biological activity, to support the safe medicinal use of plant extracts and provide guidance for future research. The Virola spp.'s ethnopharmacology, including in the treatment of stomach pain and gastric ulcers, as well as antimicrobial and tryponosomicidal activities, is attributable to the presence of a myriad of phytoconstituents, such as flavonoids, tannins, phenolic acids, lignans, arylalkanones, and sitosterol. Hence, such species yield potential leads or molecular scaffolds for the development of new pharmaceutical formulations, encouraging the elucidation of not-yet-understood action mechanisms and ascertaining their safety for humans.

Silymarin protects against radiocontrast-induced nephropathy in mice

Silymarin, an extract from Silybum marianum (milk thistle) containing a standardized mixture of flavonolignans that ameliorates some types of liver disease and, more recently, kidney damage, could be used for the ROS-scavenging effect of these antioxidants. Furthermore, contrast-induced nephropathy (CIN) is an iatrogenic impairment of renal function in patients subjected to angiographic procedures for which there is not yet a successful preventative treatment. Recent evidence has shown that this event is related to tubular/vascular injury activated mainly by oxidative stress. However, whether this bioavailable and pharmacologically safe extract protects against CIN is not clear. We proposed to evaluate the possible protective role of the antioxidant silymarin in an experimental model of CIN. Adult male Swiss mice were separated into 6 groups and pretreated orally with silymarin (50, 200 and 300 mg/kg), N-acetylcysteine (200 mg/kg) or vehicle for 5 days before the CIN and control groups. Renal function was analyzed by plasma creatinine, urea and cystatin C levels. Additionally, blood reactive oxygen species (ROS) were evaluated using ROS bioavailability, protein oxidation and DNA damage. Renal oxidative damage was evaluated using apoptosis/cell viability assays and histological analysis. We showed that silymarin preserved renal function and decreased systemic and renal oxidative damage (antigenotoxic and antiapoptotic properties, respectively) in a dose-dependent manner and was superior to conventional treatment with N-acetylcysteine. Histologically, silymarin treatment also had beneficial effects on renal glomerular and tubular injuries. Therefore, silymarin prophylaxis may be an interesting strategy for the prevention of CIN.

Worsening of Oxidative Stress, DNA Damage, and Atherosclerotic Lesions in Aged LDLr-/- Mice after Consumption of Guarana Soft Drinks

BACKGROUND

Excessive consumption of soft drinks (SD) has become a health problem worldwide due to its association with related cardiovascular diseases. We investigated the possible impacts associated with the consumption of Brazilian guarana (normal and zero) SD in dyslipidemic mice, thus mitigating potential clinical confounders such as poor-quality diet, lifestyle, body composition, and/or comorbidities.

METHODS

Sixteen-month-old LDLr-/- mice were divided into the following groups: (1) control; (2) GSD: normal guarana SD; and (3) Z-GSD: zero guarana SD. All were fed ad libitum, and blood pressure was measured noninvasively. After 8 weeks, aorta, blood, liver, and stomach samples were collected for histological and biochemical analyses.

RESULTS

Guarana soft drinks increased atherosclerosis (~60%) and were associated with hypercholesterolemia, hypertension, oxidative stress, DNA fragmentation, and apoptosis (~2-fold) of blood cells, besides presenting an increase in liver and gastric damage even in normoglycemia. Interestingly, Z-GSD did not cause the aforementioned changes, except in hemodynamic and renal parameters.

CONCLUSIONS

Chronic administration of GSD is prooxidative, compromising the cardiovascular, gastric, and hepatic systems; the effects are due at least in part to free sugar consumption but not to guarana extract per se.