Anti-inflammatory, anti-cholinergic and cytotoxic effects of Sida rhombifolia

Evidence for the efficacy of anti-inflammatory plants used in Brazilian traditional medicine with ethnopharmacological relevance

ETHNOPHARMACOLOGICAL RELEVANCE

When exacerbated, inflammatory processes can culminate in physical and emotional disorders and, if not stopped, can be lethal. The high prevalence of inflammation has become a public health problem, and the need for new drugs to treat this pathology is imminent. The use of medicinal plants has emerged as an alternative, and a survey of data that corroborates its application in inflammatory diseases is the starting point. Furthermore, Brazil harbors a megadiversity, and the traditional use of plants is relevant and needs to be preserved and carefully explored for the discovery of new medicines.

AIM OF THE STUDY

This review sought to survey the medicinal plants traditionally used in Brazil for the treatment of inflammatory processes and to perform, in an integrative way, a data survey of these species and analysis of their phytochemical, pharmacological, and molecular approaches.

MATERIALS AND METHODS

Brazilian plants that are traditionally used for inflammation (ophthalmia, throat inflammation, orchitis, urinary tract inflammation, ear inflammation, and inflammation in general) are listed in the DATAPLAMT database. This database contains information on approximately 3400 native plants used by Brazilians, which were registered in specific documents produced until 1950. These inflammatory disorders were searched in scientific databases (PubMed/Medline, Scopus, Web of Science, Lilacs, Scielo, Virtual Health Library), with standardization of DECS/MESH descriptors for inflammation in English, Spanish, French, and Portuguese, without chronological limitations. For the inclusion criteria, all articles had to be of the evaluated plant species, without association of synthesized substances, and full articles free available in any of the four languages searched. Duplicated articles and those that were not freely available were excluded.

RESULTS

A total of 126 species were identified, culminating in 6181 articles in the search. After evaluation of the inclusion criteria, 172 articles representing 40 different species and 38 families were included in the study. Comparison of reproducibility in intra-species results became difficult because of the large number of extraction solvents tested and the wide diversity of evaluation models used. Although the number of in vitro and in vivo evaluations was high, only one clinical study was found (Abrus precatorius). In the phytochemical analyses, more than 225 compounds, mostly phenolic compounds, were identified.

CONCLUSION

This review allowed the grouping of preclinical and clinical studies of several Brazilian species traditionally used for the treatment of many types of inflammation, corroborating new searches for their pharmacological properties as a way to aid public health. Furthermore, the large number of plants that have not yet been studied has encouraged new research to revive traditional knowledge.

Tetrahydroxanthene-1,3(2H)-diones and Oxidized Hexadiene Derivatives from Uvaria leptopoda and Their Biological Activities

The first phytochemical investigation of the twig extract of Uvaria leptopoda resulted in the isolation and identification of three new tetrahydroxanthene-1,3(2H)-diones, uvarialeptones A-C, two new oxidized hexadiene derivatives, uvarialeptols A and B, together with ten known compounds. Their structures were elucidated by spectroscopic techniques and mass spectrometry. Uvarialeptones A and B were unprecedented tetrahydroxanthene-1,3(2H)-dione dimers which exhibited a cyclobutane ring via [2 + 2] cycloaddition from uvarialeptone C and 9a-O-methyloxymitrone, respectively. The structure of uvarialeptone A was confirmed by X-ray diffraction analysis using Mo Kα radiation. Compound 3 inhibited NO production at an IC50 value of 6.7 ± 0.1 μM.

Ameliorative effects of Sida acuta and vitamin C on serum DNA damage, pro-inflammatory and anti-inflammatory cytokines in roosters fed aflatoxin B1 contaminated diets

The ameliorative effects of Sida acuta leaf meal (SALM) and vitamin C on the serum pro-inflammatory and anti-inflammatory cytokines as well as DNA damage of cocks fed aflatoxin B1 (AFB1) contaminated diets were examined. The experiment was a completely randomized design with a total of 250 sexually mature Isa White cocks aged 24 weeks, randomly allotted into five experimental diets; each diet contained 5 replicates with 10 roosters. The diets were A (control/basal diet), B (A + 1 mg/kg AFB1), C (B + 200 mg/kg vitamin C), D (B + 2.5 g/kg SALM) and E (B + 5.0 g/kg SALM). Fresh and clean water was also provided for the whole experimental period of twelve weeks. Inclusion of 1 mg/kg AFB1 without vitamin C or SALM increased TNF-α and IL-1β as well as 8-OHdG and NF-κB in the serum significantly (P < 0.05) among the cocks on diet B. However, the fortification of AFB1 contaminated diets with vitamin C and SALM depressed serum TNF-α, IL-1β, 8-OHdG and NF-κB concentrations of the cocks significantly (P < 0.05). Conversely, serum IL-4 and IL-10 in birds given 1 mg/kg AFB1 without vitamin C or SALM decreased significantly (P < 0.05) in comparison with the roosters on the control. However, improvements (P < 0.05) in IL-4 and IL-10 concentrations with corresponding reduction (P < 0.05) in TNF-α, IL-1β, 8-OHdG and NF-κB concentrations were recorded among cocks fed Diets C, D and E, respectively. Therefore, dietary addition of SALM at the level used in this study was beneficial and has comparable effects with inorganic antioxidant (C vitamin) by significantly reducing the inflammatory cytokines and oxidative damage biomarkers as well as enhancing the anti-inflammatory cytokines thereby promoting the health status of the cocks fed AFB1 contaminated ration.

Synthesis of benzylated amine-substituted xanthone derivatives and their antioxidant and anti-inflammatory activities

Oxidative stress and its constant companion, inflammation, play a critical part in the pathogenesis of many acute and chronic illnesses. The discovery of new multi-targeted drug candidates with antioxidant and anti-inflammatory properties is deemed necessary. Thus, a series of novel xanthone derivatives with halogenated benzyl (4b-4d, 4f-4h) and methoxylated benzyl groups (4e) attached to the butoxy amine substituent were synthesized in this study. The synthesized xanthone derivatives exhibited stronger antioxidant activity against H₂ O₂ scavenging than the standard drug, α-tocopherol, but weaker towards DPPH scavenging and ferrous ion chelation. Besides that, 4b-4d, 4f-4h demonstrated good anti-inflammatory activities through NO production inhibition towards lipopolysaccharide (LPS)-induced RAW 264.7 cells and showed 2-4 times stronger effects than the standard drug, diclofenac sodium. Moreover, compound 4b with two brominated benzyl groups attached to the butoxy amine substituent suppressed the production of pro-inflammatory cytokines, TNF-α and IL-1β, significantly. Structure-activity relationship elucidated that the halogenated benzylamine substituent plays an important role in contributing the antioxidant and anti-inflammatory activities of xanthones. In summary, xanthone 4b was identified as a potential lead compound to be further developed into antioxidant and anti-inflammatory drugs. Thus, further studies on the related mechanisms of action of 4b are recommended.

Medicinal plants utilized in the management of epilepsy in Ethiopia: ethnobotany, pharmacology and phytochemistry

Epilepsy is a common central nervous system (CNS) disorder that affects 50 million people worldwide. Patients with status epilepticus (SE) suffer from devastating comorbidities and a high incidence of mortalities. Antiepileptic drugs (AEDs) are the mainstream treatment options for the symptomatic relief of epilepsy. The incidence of refractory epilepsy and the dose-dependent neurotoxicity of AEDs such as fatigue, cognitive impairment, dizziness, attention-deficit behavior, and other side effects are the major bottlenecks in epilepsy treatment. In low- and middle-income countries (LMICs), epilepsy patients failed to adhere to the AEDs regimens and consider other options such as complementary and alternative medicines (CAMs) to relieve pain due to status epilepticus (SE). Plant-based CAMs are widely employed for the treatment of epilepsy across the globe including Ethiopia. The current review documented around 96 plant species (PS) that are often used for the treatment of epilepsy in Ethiopia. It also described the in vivo anticonvulsant activities and toxicity profiles of the antiepileptic medicinal plants (MPs). Moreover, the phytochemical constituents of MPs with profound anticonvulsant effects were also assessed. The result reiterated that a lot has to be done to show the association between herbal-based epilepsy treatment and in vivo pharmacological activities of MPs regarding their mechanism of action (MOA), toxicity profiles, and bioactive constituents so that they can advance into the clinics and serve as a treatment option for epilepsy.

Sida rhombifolia Exerts Anti-Proliferative and Pro-Apoptotic Effects in Human Liver Cancer HepG2 Cells in Vitro

PURPOSE

Modern research revealed that plants belonging to the Sida rhombifolia family (Malvaceae) contain biologically active compounds that make them prone to discovering and developing anticancer drugs. This study aimed to evaluate the apoptosis effects of S. rhombifolia extracts in HepG2 Cell Line was performed.

METHODS

The extractions were prepared, and an MTT assay was applied to evaluate its role in decreasing the viability of HepG2 and HFF cells. Phenolic compounds were analyzed using High-performance liquid chromatography (HPLC). FlowCytometry and RT-qPCR evaluated apoptosis was performed to measure the mRNA expression of pro-and anti-apoptotic mediators.

RESULTS

The results can be summarized as EtOAc extract was more cytotoxic against the HepG2 cells (IC50= 364.3 µg/mL) compared to MeOH and HEX extracts (720.2 µg/mL) (560.4 µg/mL) with less cytotoxicity in HFF cells (353.2 µg/mL). The HPLC analysis results revealed most phenolic compounds, such as Epicatechin(1.3 mg/g). The EtOAc extract (300 μg/mL) induced 34% apoptosis in HepG2 cells. RT-qPCR data showed upregulation of the proapoptotic gene (Bax) and increased Bax/BCL-2 ratio by S. rhombifolia EtOAc extract (300 μg/mL).

CONCLUSION

In conclusion, the EtOAc extract of S. rhombifolia is capable of inducing apoptosis in HepG2 cells through modulation of the mitochondrial pathway, which explains their antitumor activity.

Antioxidant, Anti-Inflammatory and Cytotoxic Activity of Phenolic Compound Family Extracted from Raspberries (Rubus idaeus): A General Review

Raspberries (Rubus idaeus) possess a wide phenolic family profile; this serves the role of self-protection for the plant. Interest in these compounds have significantly increased, since they have been classified as nutraceuticals due to the positive health effects provided to consumers. Extensive chemical, in vitro and in vivo studies have been performed to prove and validate these benefits and their possible applications as an aid when treating several chronic degenerative diseases, characterized by oxidative stress and an inflammatory response. While many diseases could be co-adjuvanted by the intake of these phenolic compounds, this review will mainly discuss their effects on cancer. Anthocyanins and ellagitannins are known to provide a major antioxidant capacity in raspberries. The aim of this review is to summarize the current knowledge concerning the phenolic compound family of raspberries, and topics discussed include their characterization, biosynthesis, bioavailability, cytotoxicity, antioxidant and anti-inflammatory activities.

Sida tuberculata: In vitro cytotoxicity and in vivo anti-inflammatory effect

ETHNOPHARMACOLOGICAL RELEVANCE

Sida tuberculata R. E. Fries (Malvaceae) is a pioneer species considered a weed in farm fields in Southern Brazil. Widely distributed in South Brazil, S. tuberculata is popularly used to treat inflammatory conditions.

AIMS OF THE STUDY

The current study aimed to assess the in vitro cytotoxic and in vivo anti-inflammatory properties of S. tuberculata.

MATERIALS AND METHODS

Initially, extracts obtained from leaves (STLE) and roots (STRE) were submitted to cytotoxicity tests using human leukocytes (non-malignant cell line) and HepG2 and MCF-7 (tumor cell lines). In sequence, anti-inflammatory properties were investigated against carrageenan-induced peritonitis model.

RESULTS

In vitro analyses displayed a significant decrease in human leukocytes viability without genotoxic damage. IC₅₀ results from tumor cells presented significant decrease in cell viability, slightly more pronounced for STRE. In addition, STLE significantly inhibited the inflammatory and oxidative parameters (TBARS, NPSH, SOD, MPO activity, cell influx, and cytokines release).

CONCLUSION

Our findings indicate S. tuberculata extracts have cytotoxic potential more pronounced on tumor cell lines, as well as leaves extract shows a significant reduction in acute inflammation process, as already reported for Sida genus and specifically for this species.

Protective Effects of Alternanthera sessilis Ethanolic Extract against TNF-α or H2O2-Induced Endothelial Activation in Human Aortic Endothelial Cells

Activation of the endothelium has been shown to contribute to the early stage of vascular diseases such as atherosclerosis and hypertension. In endothelial activation, excess reactive oxygen species (ROS) production and increased expression of cell adhesion molecules cause an increase in vascular permeability. Alternanthera sessilis (L.) R. Br. is an edible traditional herbal plant, which has previously been shown to possess antioxidant and anti-inflammatory effects. However, the effect of A. sessilis on the activation of human aortic endothelial cells (HAECs) remains unknown. This study aimed to investigate the effects of A. sessilis on endothelial permeability, vascular cell adhesion-1 (VCAM-1) expression, production of ROS and hydrogen peroxide (H₂O₂), and superoxide dismutase (SOD) and catalase (CAT) activities. The viability of HAECs was first determined using the MTT viability assay. The effect of A. sessilis on endothelial permeability was examined using the FITC-dextran permeability assay. Besides, enzyme-linked immunosorbent assay (ELISA) was done to assess soluble VCAM-1 (sVCAM-1) expression. The production of ROS and H₂O₂ was studied using 2′,7′-dichlorodihydrofluorescein diacetate (H₂-DCFDA) and Amplex Red fluorescent dyes, respectively. SOD and CAT activities were also measured using commercial kits. Our results showed that 25–200 μg/mL of A. sessilis ethanolic extract did not cause significant death in HAECs. A. sessilis at 200 μg/mL significantly inhibited TNF-α-induced hyperpermeability of HAECs. However, A. sessilis did not reduce increased VCAM-1 expression induced by TNF-α. A. sessilis also significantly reduced TNF-α-induced increased ROS production, but not H₂O₂ production. Furthermore, 100 μM of H₂O₂ decreased both SOD and CAT activities in HAECs at 2 h. A. sessilis ethanolic extract dramatically increased both reduced SOD and CAT activities caused by H₂O₂. The liquid chromatography-mass spectrometry (LC-MS) analysis of A. sessilis ethanolic extract demonstrated the presence of arachidonic acid, azadirachtin, astaxanthin, flavanole base + 3O, 2Prenyl, and vicenin 2, while the gas chromatography-mass spectrometry (GC-MS) analysis showed that the extract contains 1,3,5-dihydroxy-6-methyl-2,3-dihydro-4H-pyran-4-one, 3-deoxy-d-mannoic lactone, 4-pyrrolidinobenzaldehyde, and n-hexadecanoic acid. In conclusion, our findings suggest that A. sessilis ethanolic extract protects against endothelial hyperpermeability and oxidative stress elicited by pro-inflammatory or prooxidant stimulus. This study reveals a therapeutic potential of A. sessilis in preventing endothelial activation, which is a key event in early atherosclerosis.

Antioxidant Potential of Red Palm-Pressed Mesocarp Olein

Oxidative stress occurs due to the imbalance amount of the free radicals and antioxidants in human body which often associated with numerous chronic diseases. The antioxidant properties of red palm-pressed mesocarp olein (PPMO) have not been widely studied. Therefore, antioxidant properties of PPMO relative to commercially available edible oils, namely red palm olein (RPO), palm olein (PO), extra virgin olive oil (OO) and extra virgin coconut oil (CNO) were studied. PPMO exhibited significant higher phytonutrients which more than 2-fold compared to the edible oils. Overall, antioxidant screening indicated that PPMO has significantly higher antioxidant activities than RPO, PO and CNO in term of DPPH, H₂O₂, NO scavenging and FIC; and significantly higher H₂O₂ and FIC than OO. The outcomes of this study reveal that PPMO is as good as commercially available edible oil, also a good source for food applications and dietary nutritional supplements. More importantly, the utilization of PPMO could mitigate oil palm waste problem and results in positive environmental impact.

Preclinical safety assessment of the crude extract from Sida rhombifolia L. aerial parts in experimental models of acute and repeated-dose 28 days toxicity in rats

Sida rhombifolia (Malvaceae) is popularly used as a treatment for several pathological conditions; however, there is a lack of studies that identify its compounds and that evaluate comprehensively the safety of its consumption. Therefore, the aim of this study was to determinate the phytochemical constitution of the crude extract of Sida rhombifolia (CESR), and its safety in models of acute and repeated doses (28 days) toxicity. The tested dose for the model of acute toxicity was 2000 mg/kg doses for the repeated dose model were 150, 300 e 600 mg/kg. Hematological, biochemical, histopathological and oxidative markers were investigated. HPLC-DAD-MS analysis evidenced the presence of caffeic acid, coumarin, and rutin. In the acute toxicity model the only altered parameters were tissue ROS, and AST and BUN in serum. As for the repeated dose experiment both hematological and biochemical markers remained within the values of reference for the species. Obtained results demonstrate that the CESR did not present significant toxic effects when administrated orally to male and female rats in acute and repeated doses.

Chemical constituents of two Cameroonian medicinal plants: Sida rhombifolia L. and Sida acuta Burm. f. (Malvaceae) and their antiplasmodial activity

An extensive phytochemical investigation of the EtOH/H₂O (7:3) extracts of Sida rhombifolia L. and Sida acuta Burm. f., yielded a previously undescribed ceramide named rhombifoliamide (1) and a xylitol dimer (2), naturally isolated here for the first time, as well as the thirteen known compounds viz, oleanolic acid (3), β-amyrin glucoside (4), ursolic acid (5), β-sitosterol glucoside (6), tiliroside (7), 1,6-dihydroxyxanthone (8), a mixture of stigmasterol (9) and β-sitosterol (10), cryptolepine (11), 20-Hydroxyecdysone (12), (E)-suberenol (13), thamnosmonin (14) and xanthyletin (15). Their structures were elucidated by the analyses of their spectroscopic and spectrometric data (1 D and 2 D NMR, and HRESI-MS) and by comparison with the previously reported data. The crude extracts, fractions, and some isolated compounds were tested against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) Plasmodium falciparum strains. All the tested samples demonstrated moderate and/or significant activities against 3D7 (IC₅₀ values: 0.18-20.11 µg/mL) and Dd2 (IC₅₀ values: 0.74-63.09 µg/mL).

Potential therapeutic natural products against Alzheimer's disease with Reference of Acetylcholinesterase

Alzheimer's disease (AD), is the most common type of dementia primarily affecting the later years of life. Its prevalence is likely to increase in any aging population and will be a major burden on healthcare system by the mid of the century. Despite scientific and technological breakthroughs in the last 50 years, that have expanded our understanding of the disease on a system, cellular and molecular level, therapies that could stop or slow the progression of the disease are still unavailable. The Food and Drug Administration (FDA), has approved acetylcholinesterase (AChE) inhibitors (donepezil, galantamine, tacrine and rivastigmine) and glutamate receptor antagonist (memantine) for the treatment of AD. In this review we summarize the studies reporting phytocompounds and extracts from medicinal plants that show AChE inhibitory activities and could be of potential benefit in AD. Future research directions are suggested and recommendations made to expand the use of medicinal plants and their formulations to prevent, mitigate and treat AD.

Evaluation of the cytotoxic and genotoxic effects of Sida planicaulis Cav extract using human neuroblastoma cell line SH-SY5Y

Sida planicaulis is a weed thought to have originated in Brazil, where it is present in abundant quantities, but also this plant is also found in south-central Florida, Indian Ocean Islands, and the Pacific Islands. Sida planicaulis produces neurotoxicity that adversely affects livestock breeding with heavy animal losses and consequent negative impact on Brazil's economy. The aim of this study was to determine the chemical profile, cytotoxic and genotoxic effects of ethanolic extracts of S. planicaulis collected in winter (leaf extract) and summer (leaf extract and leaf + flower extract) using an in vitro model of human neuroblastoma cell line SH-SY5Y. Phytochemical screening demonstrated the presence of alkaloids, flavonoids, and apolar compounds. Rutin, quercetin, and swainsonine were detected by HPLC and GC/MS, respectively. Phosphorus, potassium, iron, and zinc were the inorganic elements found. Extracts produced cytotoxicity at all concentrations tested (7-4,000 μg/ml) as evidenced by the colorimetric assay [3-(4,5-dimethyl-thiazol-2-yl) -2,5-diphenyl-tetrazolium bromide (MTT)]. Based upon the alkaline comet assay extracts were found to induce genotoxicity at concentrations ranging from 0.437 to 7 μg/ml. DNA damage produced by extracts was affirmed using a modified comet assay with the enzymes Endo III and FPG in a concentration dependent manner. Further, enzyme-modified comet assay showed both oxidized purines and pyrimidines, and consequently oxidative stress was related to genomic instability and cell death. Data suggest that low concentrations of ethanolic extracts of S. planicaulis (different seasons) induced increased DNA damage related to oxidative stress and chemical composition.

Physical and Tensile Properties of Handmade Sida rhombifolia Paper

This study focuses on the production and characterization of biodegradable handmade paper from the Sida rhombifolia plant (SRP) cellulose. Sida rhombifolia plant is a seasonal plant that grows in the equatorial and tropical climates. The studies carried out on this SRP were aimed at investigating the methods required for the production of handmade paper from SRP plant and also at determining the tensile strength. Four specimens of SRP paper of different additive labels S0 (no additive), S1 (starch and KOH), S2 (starch), and S3 (Foska liquid glue) were produced using the Kraft method. Tensile properties (stress at break, elongation at break, and Young's modulus), the rate of water absorption, and the rate of moisture absorption were carried out. Results showed that the addition of potassium hydroxide considerably reduces Young's modulus of SRP handmade paper (S1) while the Foska liquid glue (S3) significantly improves it. In addition, the addition of potassium hydroxide and Foska liquid substantially improves the water absorption properties of the paper S2 and S3, respectively. The adhesive liquid creates more porosity and consequently increases the absorption of water. The addition of potassium hydroxide and Foska liquid significantly embedded the rate of moisture absorption. From the results obtained, it can be concluded that the paper S3 can be used as packaging paper since it has better mechanical properties and moisture absorption.

Sida tuberculata reduces oxidative stress and pain caused by the knee osteoarthritis

ETHNOPHARMACOLOGICAL RELEVANCE

Knee osteoarthritis (OA) cause pain and edema, as well as unbalance between the production of reactive oxygen species and antioxidant activity. These problems interfere with the articular function, leading to a significant loss of life quality. Sida tuberculata R.E.Fr. is an herbaceous plant belonging to the Malvaceae family found in southern Brazil. This plant has traditionally been consumed as an aqueous extract and popularly used in the treatment of many diseases, with antioxidant and antimicrobial activity, reducing pain and inflammation.

AIM OF THE STUDY

To verify the effects of S. tuberculata extract obtained from leaves on oxidative, toxic and nociceptive parameters induced by knee OA in rats.

MATERIALS AND METHODS

Aqueous extracts of S. tuberculata were evaluated under phytochemical analyses. Knee Osteoarthritis was induced in rats with monosodium iodoacetate (1.5 mg/50 μl) and treated with S. tuberculata extract. The animals were treated orally with 3 doses of S. tuberculata extract (STE): 1.5, 5 and 15 mg/ml, for 14 days. For biochemical analyses, the following tests were performed: lipid peroxidation, carbonylated protein content, superoxide dismutase activity, non-protein thiol levels and myeloperoxidase activity. For the evaluation of pain and edema we verify mechanical and thermal hyperalgesia, spontaneous pain observation and measurement of knee edema with a caliper. For histological evaluations, the animal knee joints were removed. For toxicity evaluation, the levels of aspartate aminotransferase, alanine aminotransferase and urea, as well as the relative weight of the organs were analyzed.

RESULTS

The S. tuberculata phytochemical analyses showed the majority peak corresponding to 20-hydroxyecdysone (20HE). The plant extract decreased damages related to oxidative stress in the blood serum (lipid peroxidation and carbonyl content) Overall, the STE 5 mg Group presented the greater statistical significance, in the blood serum samples, in relation to the other groups, being the most relevant result. The S. tuberculata groups presented pain decrease, lower neutrophil activity in the knee, and increased blood serum activity. The animals of S. tuberculata groups showed a decrease in mechanical hyperalgesia. The animals treated also presented lower scores for spontaneous pain. It was observed that the dose of 5 mg presented, once again, more expressive results, since the animals of this group had a higher frequency (greater number of days) with significant decrease of pain. In the histological analysis, in the STE 5 mg group, the articular cartilage lesions were observed at an intermediate point between the damage found in the MIA and Diclofenac groups. Besides that, the STE did not show significant changes in oxidative stress damage in liver and kidney samples. Blood serum samples did not indicate significant differences in liver and renal function. As well as, there were no differences in mean relative body weights in relation to control groups (Salina and MIA).

CONCLUSION

S. tuberculata reduced the damage due to oxidative stress and pain caused by knee osteoarthritis in rats. In addition, the extract presented no toxicity. Our results suggest that S. tuberculata seems to have a therapeutic potential in the osteoarthritis treatment.

Sida tuberculata extract reduces the nociceptive response by chemical noxious stimuli in mice: Implications for mechanism of action, relation to chemical composition and molecular docking

Sida tuberculata R.E.Fr. (Malvaceae) is a medicinal plant widely found in Southern Brazil, and popularly used for inflammatory disorders and to pain relief. A phytochemical analysis followed by an investigation about antinociceptive potential and mechanism of action were performed with leaves and roots extracts. Methanolic extracts, designated as S. tuberculata leaves extract (STLE) and S. tuberculata roots extract, were analyzed both by UHPLC–MS. The in vivo antinociceptive potential of STLE (10–300 mg kg−1) was assessed in mice subjected to the acetic acid‐induced abdominal writhes and formalin model. Agonist/antagonist tests and computational docking suggest the involvement of opioid and adenosinergic systems. The main chemical class detected on extracts was the ecdysteroids, and 20‐hydoxyecdysone (20HE) was confirmed as the major phytoconstituent. The pretreatment with STLE (100 mg kg−1) reduced more than 70% abdominal contortions induced by acetic acid model and produced significant inhibition on formalin‐induced licking response. The mechanism of action study revealed STLE might act through opioid and adenosine systems. Molecular docking suggested kaempferol derivative and 20HE might interacting with μ‐opioid receptor. Thus, the results suggest the existence of antinociceptive potential from S. tuberculata extracts being in accordance to the traditional use.

Ethnomedicinal, Phytochemical and Ethnopharmacological Aspects of Four Medicinal Plants of Malvaceae Used in Indian Traditional Medicines: A Review

The ethnomedicinal values of plants form the basis of the herbal drug industry. India has contributed its knowledge of traditional system medicines (Ayurveda and Siddha) to develop herbal medicines with negligible side effects. The World Health Organization has also recognized the benefits of drugs developed from natural products. Abutilon indicum, Hibiscus sabdariffa, Sida acuta and Sida rhombifolia are ethnomedicinal plants of Malvaceae, commonly used in Indian traditional system of medicines. Traditionally these plants were used in the form of extracts/powder/paste by tribal populations of India for treating common ailments like cough and cold, fever, stomach, kidney and liver disorders, pains, inflammations, wounds, etc. The present review is an overview of phytochemistry and ethnopharmacological studies that support many of the traditional ethnomedicinal uses of these plants. Many phytoconstituents have been isolated from the four ethnomedicinal plants and some of them have shown pharmacological activities that have been demonstrated by in vivo and/or in vitro experiments. Ethnomedicinal uses, supported by scientific evidences is essential for ensuring safe and effective utilization of herbal medicines.