Antinociceptive and anti-inflammatory activity of Sida rhomboidea leaves

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.

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

CONTEXT

Sida (Malvaceae) has been used as a traditional remedy for the treatment of diarrhoea, malarial, gastrointestinal dysentery, fevers, asthma and inflammation.

OBJECTIVES

This study evaluates the anti-inflammatory, cytotoxic and anti-cholinergic activities of Sida rhombifolia Linn. whole plant for the first time.

MATERIALS AND METHODS

S. rhombifolia whole plant was extracted by n-hexane, ethyl acetate and methanol using Soxhlet apparatus. The plant extracts were evaluated for their antioxidant (DPPH, FIC and FRAP), anti-inflammatory (NO and protein denaturation inhibitions), cytotoxic (MTT) and anti-cholinesterase (AChE) properties in a range of concentrations to obtain IC₅₀ values. GC-MS analysis was carried out on the n-hexane extract.

RESULTS AND DISCUSSION

The ethyl acetate extract exhibited the most significant antioxidant activities by scavenging DPPH radicals and ferrous ions with EC₅₀ of 380.5 and 263.4 μg/mL, respectively. In contrast, the n-hexane extract showed the strongest anti-inflammatory activity with IC₅₀ of 52.16 and 146.03 μg/mL for NO and protein denaturation inhibition assays, respectively. The same extract also revealed the strongest effects in anti-cholinesterase and cytotoxic tests at the concentration of 100 μg/mL, AChE enzyme inhibition was 58.55% and human cancer cells, SNU-1 and Hep G2 inhibition was 68.52% and 47.82%, respectively. The phytochemicals present in the n-hexane extract are palmitic acid, linoleic acid and γ-sitosterol.

CONCLUSIONS

The present study revealed that the n-hexane extract possessed relatively high pharmacological activities in anti-inflammation, cytotoxicity and anti-cholinesterase assays. Thus, further work on the detail mechanism of the bioactive phytochemicals which contribute to the biological properties are strongly recommended.

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.

The genus Sida L. - A traditional medicine: Its ethnopharmacological, phytochemical and pharmacological data for commercial exploitation in herbal drugs industry

ETHNOPHARMACOLOGICAL RELEVANCE

Sida L. (Malvaceae) has been used for centuries in traditional medicines in different countries for the prevention and treatment of different diseases such as diarrhea, dysentery, gastrointestinal and urinary infections, malarial and other fevers, childbirth and miscarriage problems, skin ailments, cardiac and neural problems, asthma, bronchitis and other respiratory problems, weight loss aid, rheumatic and other inflammations, tuberculosis, etc.

AIMS OF THIS REVIEW

To assess the scientific evidence for therapeutic potential of Sida L. and to identify the gaps of future research needs.

METHODS

The available information on the ethnomedicinal uses, phytochemistry, pharmacology and toxicology of Sida species was collected via a library and electronic searches in SciFinder, PubMed, ScienceDirect, Google Scholar for the period, 1933-2015.

RESULTS

A variety of ethnomedicinal uses of Sida species have been found in India, China, Afrian and American countries. Phytochemical investigation of this genus has resulted in identification of about 142 chemical constituents, among which alkaloids, flavonoids and ecdysteroids are the predominant groups. The crude extracts and isolates have exhibited a wide spectrum of in vitro and in vivo pharmacological effects involving antimicrobial, analgesic, anti-inflammatory, abortifacient, neuroprotective, cardiovascular and cardioprotective, antimalarial, antitubercular, antidiabetic and antiobesity, antioxidant and nephroprotective activities among others. Ethnopharmacological preparations containing Sida species as an ingredient in India, African and American countries possess good efficacy in health disorders. From the toxicity perspective, only three Sida species have been assessed and found safe for oral use in rats.

CONCLUSIONS

Pharmacological results supported some of the uses of Sida species in the traditional medicine. Alkaloids, flavonoids, other phenolics and ecdysteroids were perhaps responsible for the activities of extracts of the plants of this genus. No clinical study was reported. The detailed study on mechanism of action of isolates and extracts and their clinical study are needed for their use in modern medicine. More attention should be paid to Sida acuta, Sida cordifolia, Sida spinosa, Sida rhombifolia and Sida veronicaefolia in the domain of diarrhea, dysentery, gastrointestinal and urinary infections, skin ailments, asthma, bronchitis and other respiratory problems, malaria, childbirth and miscarriage problems, cardiac and neural problems, weight loss aid, and rheumatic and other inflammations, etc. Furthermore, detailed study on quality and safety assurance data on available ethnopharmacological preparations is needed for their commercial exploitation in local and global markets.

Ethnomedicinal plants used by traditional healers in Phatthalung Province, Peninsular Thailand

BACKGROUND

In rural communities of Thailand, traditional healers still play an important role in local health care systems even though modern medicine is easily accessible. Meanwhile, natural forests in Thailand which are important sources of materia medica are being greatly destroyed. This has led to an erosion of traditional Thai medicine. Furthermore, the concept of medicinal plant selection as medicine based on their tastes is still an important component of traditional Thai medicine, but no or little publications have been reported. Thus the aim of the present study is to collect ethnomedicinal data, medicinal plant tastes and relevant information from experienced traditional healers before they are lost.

METHODS

An ethnobotanical survey was carried out to collect information from nine experienced traditional healers on the utilization of medicinal plants in Phatthalung Province, Peninsular Thailand. Data were obtained using semi-structured interviews and participant observations. Plant specimens were also collected and identified according to the plant taxonomic method.

RESULTS

A total of 151 medicinal plants were documented and 98 of these are reported in the study. Local names, medicinal uses, parts used, modes of preparation, and the relationship between ailments and tastes of medicinal plant species are presented.

CONCLUSIONS

This research suggests that traditional healers are still considered important for public health among Thai communities and that many people trust the healing properties of medicinal plants. In the future, it is hoped that traditional Thai medicine will be promoted and therefore will help reduce national public health expense.

In vitro antibacterial activity and acute toxicity studies of aqueous-methanol extract of Sida rhombifolia Linn. (Malvaceae)

BACKGROUND

Many bacteria among the Enterobacteria family are involved in infectious diseases and diarrhoea. Most of these bacteria become resistant to the most commonly used synthetic drugs in Cameroon. Natural substances seem to be an alternative to this problem. Thus the aim of this research was to investigate the in vitro antibacterial activity of the methanol and aqueous-methanol extracts of Sida rhombifolia Linn (Malvaceae) against seven pathogenic bacteria involved in diarrhoea. Acute toxicity of the most active extract was determined and major bioactive components were screened.

METHODS

The agar disc diffusion and the agar dilution method were used for the determination of inhibition diameters and the Minimum Inhibitory Concentration (MICs) respectively. The acute toxicity study was performed according WHO protocol.

RESULTS

The aqueous-methanol extract (1v:4v) was the most active with diameters of inhibition zones ranging from 8.7 - 23.6 mm, however at 200 microg/dic this activity was relatively weak compared to gentamycin. The MICs of the aqueous-methanol extract (1v:4v) varied from 49.40 to 78.30 microg/ml. Salmonella dysenteriae was the most sensitive (49.40 microg/ml). For the acute toxicity study, no deaths of rats were recorded. However, significant increase of some biochemical parameters such as aspartate amino-transferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and creatinine (CRT) were found. The phytochemical analysis of the aqueous methanol extract indicated the presence of tannins, polyphenols, alkaloids, glycosides, flavonoids and saponins

CONCLUSION

The results showed that the aqueous-methanol extract of S. rhombifolia exhibited moderate antibacterial activity. Some toxic effects were found when rats received more than 8 g/kg bw of extract.

Cardioprotective effect of Sida rhomboidea. Roxb extract against isoproterenol induced myocardial necrosis in rats

The present study investigates cardioprotective effect of Sida rhomboidea. Roxb (SR) extract on heart weight, plasma lipid profile, plasma marker enzymes, lipid peroxidation, endogenous enzymatic and non-enzymatic antioxidants and membrane bound ATPases against isoproterenol (IP) induced myocardial necrosis (MN) in rats. Rats treated with IP (85 mg/kg, s.c.) recorded significant (p<0.05) increment in heart weight, plasma lipid profile, plasma marker enzymes of cardiac damage, cardiac lipid peroxidation (LPO) and activity levels of Ca(+2) ATPase whereas there was significant (p<0.05) decrease in plasma HDL, cardiac endogenous enzymatic and non-enzymatic antioxidants, Na(+)-K(+) ATPase and Mg(+2) ATPase. Pre-treatment with SR extract (400 mg/kg per day, p.o.) for 30 consecutive days followed by IP injections on days 29th and 30th, showed significant (p<0.05) decrease in heart weight, plasma lipid profile, plasma marker enzymes of cardiac damage, cardiac lipid peroxidation, Ca(+2) ATPase and significant increase in plasma HDL, cardiac endogenous enzymatic and non-enzymatic antioxidants, Na(+)-K(+) ATPase and Mg(+2) ATPase compared to IP treated group. Hence, this study is the first scientific report on cardioprotective effect of SR against IP induced MN in rats.