Anti-inflammatory, antioxidant and hepatoprotective effects of Thunbergia laurifolia Linn. on experimental opisthorchiasis

Antioxidative and Antimycotoxigenic Efficacies of Thunbergia laurifolia Lindl. for Addressing Aflatoxicosis in Cherry Valley Ducks

This study aimed to assess the effectiveness of aflatoxin B1 (AFB1) and Thunbergia laurifolia extract (TLE) in the diets of Cherry Valley ducklings. Our investigation covered growth indicators, blood biochemical indices, meat quality, intestinal morphology, immune response, and CP450 enzyme-related gene expression. We conducted the study with 180 seven-day-old Cherry Valley ducks, randomly divided into five dietary treatments. These treatments included a basal diet without AFB1 (T1 group), TLE, or a commercial binder; the basal diet containing 0.1 mg AFB1/kg (T2 group), 0.1 mg AFB1/kg and 100 mg TLE/kg (T3 group), 0.1 mg AFB1/kg and 200 mg TLE/kg (T4 group), and 0.1 mg AFB1/kg and 0.5 g/kg of a commercial binder (T5 group), respectively. Ducklings fed with the T2 diet exhibited lower final body weight (BW), average body weight gain (ADG), and poor feed conversion ratio (FCR) during the 42-day trials. However, all ducklings in the T3, T4, and T5 groups showed significant improvements in final BW, ADG, and FCR compared to the T2 group. Increased alanine transaminase (ALT) concentration and increased expression of CYP1A1 and CYP1A2 indicated hepatotoxicity in ducklings fed the T2 diet. In contrast, ducklings fed T3, T4, and T5 diets all showed a decrease in the expression of CYP1A1 and CYP1A2, but only the T4 treatment group showed improvement in ALT concentration. AFB1 toxicity considerably raised the crypt depth (CD) in both the duodenum and jejunum of the T2 group, while the administration of 200 mg TLE/kg (T4) or a commercial binder (T5) effectively reduced this toxicity. Additionally, the villus width of the jejunum in the T2 treatment group decreased significantly, while all T3, T4, and T5 groups showed improvement in this regard. In summary, T. laurifolia extract can detoxify aflatoxicosis, leading to growth reduction and hepatic toxicosis in Cherry Valley ducklings.

Medicinal plants used for the management of respiratory diseases in Zimbabwe: Review and perspectives potential management of COVID-19

Respiratory diseases have in the recent past become a health concern globally. More than 523 million cases of coronavirus disease (COVID19), a recent respiratory diseases have been reported, leaving more than 6 million deaths worldwide since the start of the pandemic. In Zimbabwe, respiratory infections have largely been managed using traditional (herbal) medicines, due to their low cost and ease of accessibility. This review highlights the plants' toxicological and pharmacological evaluation studies explored. It seeks to document plants that have been traditionally used in Zimbabwe to treat respiratory ailments within and beyond the past four decades. Extensive literature review based on published papers and abstracts retrieved from the online bibliographic databases, books, book chapters, scientific reports and theses available at Universities in Zimbabwe, were used in this study. From the study, there were at least 58 plant families comprising 160 medicinal plants widely distributed throughout the country. The Fabaceae family had the highest number of medicinal plant species, with a total of 21 species. A total of 12 respiratory ailments were reportedly treatable using the identified plants. From a total of 160 plants, colds were reportedly treatable with 56, pneumonia 53, coughs 34, chest pain and related conditions 29, asthma 25, tuberculosis and spots in lungs 22, unspecified respiratory conditions 20, influenza 13, bronchial problems 12, dyspnoea 7, sore throat and infections 5 and sinus clearing 1 plant. The study identified potential medicinal plants that can be utilised in future to manage respiratory infections.

Evaluation of the Intestinal Permeability of Rosmarinic Acid from Thunbergia laurifolia Leaf Water Extract in a Caco-2 Cell Model

Thunbergia laurifolia (TL) has been traditionally used as an antidote and an antipyretic drug by folk healers for centuries in Thailand. Rosmarinic acid (RA) is major compound in TL extract and has attracted great interest due to its potential broad pharmacological effects. Herein, the permeability of RA was investigated in TL extract and as a pure compound in a Caco-2 cell model by using high-performance liquid chromatography with a photodiode array detector (HPLC-PDA). The results reveal that the apparent permeability coefficient (Papp) values of RA in TL extracts and pure RA significantly increased after deconjugation by β-glucuronidase/sulfatase enzymes. Our findings exhibit possible saturable biotransformation of RA and/or membrane transport while penetrated through Caco-2 cells. The cumulative amounts of RA as pure compounds and in TL extracts increased with the exposure time, and the efflux ratio (ER) was 0.27-1.14. RA in the TL extract has a similar absorption in the conjugated form and in the pure compound. The intestinal absorption of them is through passive diffusion. Therefore, our findings conclude that the intestinal transport of RA in TL extracts was mainly penetrated as conjugated forms with glucuronic acid and/or sulfate across Caco-2 cells and transported via passive diffusion.

Thunbergia laurifolia aqueous leaf extract ameliorates paraquat-induced kidney injury by regulating NADPH oxidase in rats

We aim to study the antioxidant ability of Thunbergia laurifolia (TL) aqueous leaf extract against PQ-induced kidney injury. Rats were divided into four groups (n = 4 per group): control group, the rats received subcutaneous injection of 1 ml/kg body weight (BW) normal saline; PQ group, the rats received subcutaneous injection of 18 mg/kg BW paraquat dichloride; PQ + TL-low dose (LD) group, the rats received subcutaneous injection of 18 mg/kg BW paraquat dichloride and were orally gavaged with TL leaf extract (100 mg/kg BW); and PQ + TL-high dose (HD) group, the rats received subcutaneous injection of 18 mg/kg BW paraquat dichloride and were orally gavaged with TL leaf extract (200 mg/kg BW). This study analyzed blood urea nitrogen (BUN) and creatinine levels, renal malondialdehyde (MDA) levels, kidney histopathology, mRNA expressions of renal NADPH oxidase (NOX) and protein expressions of renal NOX-1 and NOX-4 using immunohistochemistry. The PQ group showed a significant increase in BUN and creatinine levels, renal MDA level, and a upregulation of the mRNA expression of renal NOX compared with the control group. It also demonstrated mild hydropic degeneration of the tubules. Immunohistochemistry displayed a significant increase in the protein expressions of renal NOX-1 and NOX-4 compared with the control group. TL aqueous leaf extract especially in the high dose group significantly reduced the BUN and creatinine levels, the renal MDA level, and downregulated the mRNA expression of renal NOX and protein expressions of renal NOX-1 and NOX-4 compared with the PQ group. Furthermore, it can improve PQ-induced kidney injury. TL aqueous leaf extract can ameliorate PQ-induced kidney injury by regulating oxidative stress through inhibiting NOX, especially NOX-1 and NOX-4 expressions.

Aqueous Thunbergia laurifolia leaf extract alleviates paraquat-induced lung injury in rats by inhibiting oxidative stress and inflammation

Background

Paraquat (PQ) has been reported to have a high mortality rate. The major target organ of PQ poisoning is the lungs. The pathogenesis of PQ-induced lung injury involves oxidative stress and inflammation. Unfortunately, there is still no effective antidote for PQ poisoning. We hypothesized that aqueous Thunbergia laurifolia (TL) leaf extract is a possible antidote for PQ-induced lung injury.

Methods

The total phenolic content and caffeic acid content of an aqueous extract of TL leaves were analyzed. Male Wistar rats were randomly divided into four groups (n = 4 per group): the control group (administered normal saline), the PQ group (administered 18 mg/kg body weight (BW) PQ dichloride subcutaneously), the PQ + TL-low-dose (LD) group (administered PQ dichloride subcutaneously and 100 mg/kg BW aqueous TL leaf extract by oral gavage) and the PQ + TL-high-dose (HD) group (administered PQ dichloride subcutaneously and 200 mg/kg BW aqueous TL leaf extract by oral gavage). Malondialdehyde (MDA) levels and lung histopathology were analyzed. In addition, the mRNA expression of NADPH oxidase (NOX), interleukin 1 beta (IL-1β), and tumor necrosis factor alpha (TNF-α) was assessed using reverse transcription-polymerase chain reaction (RT-PCR), and the protein expression of IL-1β and TNF-α was analyzed using immunohistochemistry.

Results

The total phenolic content of the extract was 20.1 ± 0.39 μg gallic acid equivalents (Eq)/mg extract, and the caffeic acid content was 0.31 ± 0.01 μg/mg. The PQ group showed significantly higher MDA levels and NOX, IL-1β and TNF-α mRNA expression than the control group. Significant pathological changes, including alveolar edema, diffuse alveolar collapse, hemorrhage, leukocyte infiltration, alveolar septal thickening and vascular congestion, were observed in the PQ group compared with the control group. However, the aqueous TL leaf extract significantly attenuated the PQ-induced increases in MDA levels and NOX, IL-1β and TNF-α expressions. Moreover, the aqueous TL leaf extract ameliorated PQ-induced lung pathology.

Conclusion

This study indicates that aqueous TL leaf extract can ameliorate PQ-induced lung pathology by modulating oxidative stress through inhibition of NOX and by regulating inflammation through inhibition of IL-1β and TNF-α expressions. We suggest that aqueous TL leaf extract can be used as an antidote for PQ-induced lung injury.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03567-4.

Thunbergia laurifolia leaf extract partially recovers lead-induced renotoxicity through modulating the cell signaling pathways

This research investigated the reno-protective effect of Thunbergia laurifolia Linn. (TL) in a lead-induced toxicity test through the modulation of cell signaling pathways. The study carried out to evaluate the effect of TL leaf extracts in Swiss Albino mice exposed to lead acetate (PbAc). Prior to in vivo study, a probable kidney-protective effect of the plant leaf extract was presumed through an activity-specific (PASS) molecular docking analysis. In animal model study, albino mice were divided in seven groups and co-treated with PbAc and TL (100, 200 mg/kgBW) or vitamin E (100 mg/kgBW) for 38 days, whereas the untreated control, TL control, and vehicle control groups received sodium acetate, PbAc, sodium acetate plus mineral oil, respectively. At the end of treatment, blood and kidney tissue were collected for investigating Pb concentration, estimating biochemical profile, evaluating oxidative stress and inflammatory parameters. The histopathological change of kidney along with apoptosis was assessed from kidney sections using H & E staining and TUNEL assay. Pb-exposed mice were found to be increased concentration of Pb in the blood and kidney sample, which further led to increased MDA levels in the plasma, blood, and tissue. Followed by kidney damage, increased expression of TNF-α, iNOS, and COX-2 in kidney tissues were noticed, which were related to elevated TNF-α in the systemic circulation of Pb-treated mice. Co-treatment with TL or vitamin E significantly reduced altered structure and apoptosis of kidney tissues. Downregulation of inflammatory markers especially TNF-α, iNOS, and COX-2 with simultaneous improvement of renal function through reduced plasma BUN and creatinine levels demonstrate that TL act as a potential dietary supplement to detoxify Pb in kidney showing an antioxidant and anti-inflammatory effect.

Current and Novel Therapies Against Helminthic Infections: The Potential of Antioxidants Combined with Drugs

Infections caused by Schistosoma haematobium and Opisthorchisviverrini are classified as Group 1 biological carcinogen and it has been postulated that parasites produce oxysterol and estrogen-like metabolites that might be considered as initiators of infection-associated carcinogenesis. Chemotherapy for these helminthic infections relies on a single drug, praziquantel, (PZQ) that mainly targets the parasite. Additionally, PZQ has some major drawbacks as inefficacy against juvenile form and alone it is not capable to counteract pathologies associated to infections or prevent carcinogenesis. There is an urgent need to develop novel therapeutic approaches that not only target the parasite but also improve the pathologies associated to infection, and ultimately, counteract or/and prevent the carcinogenesis processes. Repurposing the drug in combination of compounds with different modes of action is a promising strategy to find novel therapeutics approaches against these helminthic infections and its pathologies. Here, we emphasized that using antioxidants either alone or combined with anthelmintic drugs could ameliorate tissue damage, infection-associated complications, moreover, could prevent the development of cancer associated to infections. Hence, antioxidants represent a potential adjuvant approach during treatment to reduce morbidity and mortality. Despite the success of some strategies, there is a long way to go to implement novel therapies for schistosomiasis.

Approach to preserve phenolics in Thunbergia laurifolia leaves by different drying treatments

Different drying methods and blanching were investigated as to their effects on antioxidant and oxidase activities of Thunbergia laurifolia leaves. Results showed that oven-drying had the highest degradation of total phenolic content (TPC) and antioxidant activity at >85%, while freeze-drying had the lowest at <20%. However, inactivation of oxidase enzymes by blanching at 100°C resulted in a lesser decrease in TPC for oven-drying at 50 and 100°C (51% and 65%, respectively), indicating the importance of inactivating the oxidase enzymes for lower degradation of phenolics on drying. The high-performance liquid chromatography analysis showed that its major antioxidant, rosmarinic acid, degraded tremendously in the presence of oxidase enzymes, but only degraded slightly upon inactivation of oxidase enzymes. Hence, this work showed that by controlling the enzymatic activity, the preservation of phenolics with specific bioactivity in herbal tea leaves can be achieved. PRACTICAL APPLICATIONS: Thunbergia laurifolia leaves have been frequently consumed in the form of a tea or pill due to its medicinal properties. Processing of fresh herbal plant leaves by drying is required to preserve antioxidant phenolic compounds and quality of the plant leaves. Although the drying effects on the antioxidant properties have been studied, the factors that cause the change in properties have not been investigated in-depth. Controlling the factors that affect the phenolic content can help to preserve the beneficial antioxidants when processing the leaves by drying. The result of this study will be of relevance and beneficial to the herbal tea industry.

Studyng the effects of Cantharellus cibarius fungi on Opisthorchis felineus trematode and on parasite host - C57BL/6 inbred mice

Opisthorchiasis is a dangerous parasitic disease caused by trematodes in the family Opisthorchiidae. One of the causes of this infection is the species Opisthorchis felineus, which is common in the Russian Federation and Western Europe. The disease has a large number of complications and relatively few effective treatments, so nowadays it is relevant to look for new drugs for the treatment of opisthorchiasis, with the maximum antiparasitic and minimal side effect. In this work, a potentially anthelmintic effect of the methanol extract of the golden chanterelle mushroom (Cantharellus cibarius) was investigated. In in vitro experiments, the significantly reduced mobility and survival rates of juvenile O. felineus specimens with increasing concentrations (10-1000 pg/ml) of the C. cibarius extract were shown. In in vivo studies, administration of the C. cibarius extract on the first day after parasitic infection of inbred C57BL/6 mice resulted in a decrease of the number of helminths in the bile ducts of the liver, evaluated 6 weeks after infection. In another series of experiments, administration of the C. cibarius extract for 7 days to mice infected with O. felineus for five weeks had no anthelmintic effect. In both cases, the state of the infected hosts, evaluated by a number of physiological and biochemical parameters (relative weight of organs, blood indices), did not deteriorate, indicating that there was no adverse effect of the C. cibarius extract. The results obtained suggest that the C. cibarius extract might have anthelmintic properties if applied as parasite larvae excyst.

Novel bioactive peptides demonstrating anti-dengue virus activity isolated from the Asian medicinal plant Acacia Catechu

The therapeutic activities of food-derived bioactive proteins and peptides are attracting increased attention within the research community. Medicinal plants used in traditional medicines are an excellent source of bioactive proteins and peptides, especially those traditionally prepared by water extraction for use as tea or food supplement. In this study, novel bioactive peptides were isolated from enzymatic digests of 33 Thai medicinal plants. The inhibitory activity of each against dengue virus (DENV) infection was investigated. Of 33 plants, peptides from Acacia catechu extract demonstrated the most pronounced anti-DENV activity. Half maximal inhibitory concentration of 0.18 μg/ml effectively inhibited DENV foci formation. Treatment with 1.25 μg/ml crude peptide extract could reduce virus production less than 100-fold with no observable cell toxicity. Peptide sequences were determined by high-performance liquid chromatography and liquid chromatography-tandem mass spectrometry. Two bioactive peptides isolated from Acacia catechu inhibited DENV foci formation >90% at the concentration of 50 μM; therefore, they are recommended for further investigation as antiviral peptides against DENV infection.

Understanding cancer and its treatment in Thai traditional medicine: An ethnopharmacological-anthropological investigation

ETHNOPHARMACOLOGICAL RELEVANCE

Thai traditional medicine (TTM) is widely practiced in Thailand and continues to gain importance in cancer management, but little is known about the TTM practitioners' emic concepts and practice.

AIM OF THE STUDY

With this study we firstly aim to document the practice of cancer treatment and prevention by TTM practitioners and, secondly, to evaluate how such traditional concepts and practices are correlated with biomedical ones. This in turn can form the basis for developing novel strategies for designing pharmacological experiments and longer term strategies to develop TTM practice.

METHODS

Semi-structured interviews with 33 TTM practitioners were performed in five provinces in different regions of Thailand. The following information were recorded; basic information of informants, descriptions of cancer (mareng in Thai), causes, diagnosis, treatment, and prevention. Plants used in the treatment and prevention of mareng were also collected.

RESULTS

Using an in depth ethnographic approach four representative case studies to assist in a better understanding of the characteristics of mareng, its diagnosis, treatment, and prevention are reported here. Five characteristics of mareng - waste accumulation (khong sia), chronic illnesses (krasai), inflammation (kan aksep), bad blood (luead) and lymph (namlueang), and the imbalance of four basic elements (dhātu si) - have been identified. Explanatory models of cancer in TTM were linked with biomedical concepts and relevant pharmacological actions. Traditional uses and available scientific evidence of medicinal plants mentioned in the case studies for the treatment or prevention of mareng are presented and discussed.

CONCLUSION

Here for the first time five main characteristics of cancer based on Thai traditional medical concepts are analysed. Our findings are relevant not only for the planning of clinical studies or pharmacological experiment in the search for novel compounds for cancer treatment and prevention, but also for the integration of Thai traditional medicine in cancer care.

Synergistic Effect of Forbesione From Garcinia hanburyi in Combination with 5-Fluorouracil on Cholangiocarcinoma

Background: Chemotherapy for advanced cholangiocarcinoma (CCA) is largely ineffective; thus innovative combinations of chemotherapeutic agents and natural compounds represent a promising strategy. This study aimed to investigate the synergistic effects of forbesione combined with 5-fluorouracil (5-FU) in hamster cholangiocarcinoma (Ham-1) cells both in vitro and in vivo. The anti-tumor effects of 5-FU combined with forbesione in vitro were determined using the Sulforhodamine B (SRB) assay and the effects in vivo were assessed in transplanted Ham-1 allograph models. Using ethidium bromide/acridine orange (EB/AO) staining, the morphological changes of apoptotic cells was investigated. The expressions of apoptosis-related molecules after combined treatment with forbesione and 5-FU were determined using real-time RT-PCR and western blot analysis. Forbesione or 5-FU alone inhibited proliferation of Ham-1 cells in a dose-dependent manner and their combination showed a synergistic proliferation inhibitory effect in vitro. In vivo studies, forbesione in combination with 5-FU exhibited greater inhibition of the tumor in the hamster model compared with treatment using either drug alone. Forbesione combined with 5-FU exerted stronger apoptotic induction in Ham-1 cells than did single drug treatment. The combination of drugs strongly suppressed the expression of B-cell lymphoma 2 (Bcl-2) and procaspase-3 while enhancing the expression of p53, Bcl-2-associated X protein (Bax), apoptotic protease activating factor-1 (Apaf-1), caspase-9 and caspase-3, compared with single drug treatments. These results explained the decreased expression of cytokeratin 19 (CK19) positive cells and proliferation cell nuclear antigen (PCNA) positive cells in Ham-1 cell tumor tissues of the treated hamsters. There was no apparent systemic toxicity observed in the treated animals compared with the control groups. Forbesione combined with 5-FU strongly induced apoptosis in Ham-1 cells. The growth inhibitory effect of combined treatment using these two drugs was much greater than treatment with either drug alone, both in vitro and in vivo.

Antitumor effect of forbesione isolated from Garcinia hanburyi on cholangiocarcinoma in vitro and in vivo

Cholangiocarcinoma (CCA) is a malignancy with no effective therapy and poor prognosis. Forbesione, a caged xanthone isolated from Garcinia hanburyi, has been reported to inhibit proliferation and to induce apoptosis in human CCA cell lines. The present study aimed to further explore the potential anticancer properties of forbesione by testing its effects against the hamster CCA cell line Ham-1 in vitro and in vivo. It was observed that forbesione inhibited the growth of Ham-1 cells in vitro and suppressed Ham-1 growth as allograft in hamsters by inducing cell cycle arrest at the S phase. This was mediated by decreasing the protein expression of cyclin E, cyclin A and cyclin-dependent kinase 2. In addition, increased expression of p21 and p27 was detected, which could possibly explain the reduced expression of proliferating cell nuclear antigen and of the bile duct cell marker cytokeratin 19 observed in forbesione-treated Ham-1 cells in vitro and in tumor tissues of forbesione-treated hamsters. Furthermore, forbesione induced apoptosis through multiple pathways. The death receptor pathway was activated by increased expression of Fas, Fas-associated death domain and activated caspase-3, along with decreased expression of procaspase-8 and procaspase-3. The mitochondrial pathway was driven by increased expression of B-cell lymphoma (Bcl)-2-like protein 4, activated caspase-9 and inhibitor of κB-α, along with decreased expression of Bcl-2, survivin, procaspase-9 and nuclear factor-κB/p65. The endoplasmic reticulum pathway was stimulated by increased expression of activated caspase-12 and decreased expression of procaspase-12. No side effects or toxicity were observed in forbesione-treated hamsters. Thus, forbesione is a potential drug candidate for cancer therapy that deserves further investigation.

Evaluation of wound healing activity of Thunbergia laurifolia supercritical carbon dioxide extract in rats with second-degree burn wounds

Thunbergia laurifolia Lindl (TL) has been traditionally used as an antidote, anti-inflammatory, and anti-drug addiction. This study investigated the burn wound healing activity of TL leaf extract (TLL) from supercritical CO₂ extraction in rats. The extract was prepared to 2.5%, 5%, and 10% gel (TLL gel). Rats were induced to second-degree burn wounds. They were randomly divided into six groups (six rats/group), which five groups were topically applied gel base, 1% silver sulfadiazine gel, 2.5%, 5%, and 10% TLL gel, respectively, for 14 days. Six untreated burn rats were used as the control group. The rats in each group were evaluated for wound healing rate, histological parameters, and wound collagen content. Rats treated with 10% TLL gel had a higher wound healing rate than rats in the control and untreated groups. An increase in collagen content, which indicates good regeneration of wound skin, was observed in the TLL treated rats from a pathological study by Masson's trichrome and collagen content assay. The results from this study suggest that T. laurifolia leaf extract obtained by supercritical CO₂ extraction promotes the recovery of wound skin by shortening the inflammation phase, increasing collagen content, and stimulating fibroblasts proliferation and migration in wound healing.

Radical intermediate generation and cell cycle arrest by an aqueous extract of Thunbergia Laurifolia Linn. In human breast cancer cells

Thunbergia Laurifolia Linn. (TL) is one of the most familiar plants in Thai traditional medicine that is used to treat various conditions, including cancer. However, the antitumor activity of TL or its constituents has never been reported at the molecular level to support the folklore claim. The present study was designed to investigate the antitumor effect of an aqueous extract of TL in human breast cancer cells and the possible mechanism(s) of action. An aqueous crude extract was prepared from dried leaves of TL. Folin-Ciocalteu colorimetric assays were used to determine the total phenolic content. Antiproliferative and cell cycle effects were evaluated in human breast adenocarcinoma MCF-7 cells by MTT reduction assay, cell growth inhibition, clonogenic cell survival, and flow cytometric analysis. Free radical generation by the extracts was detected using electron paramagnetic resonance spectroscopy. The exposure of human breast adenocarcinoma MCF-7 cells to a TL aqueous extract resulted in decreases in cell growth, clonogenic cell survival, and cell viability in a concentration-dependent manner with an IC50 value of 843 μg/ml. Treatments with extract for 24 h at 250 μg/ml or higher induced cell cycle arrest as indicated by a significant increase of cell population in the G1 phase and a significant decrease in the S phase of the cell cycle. The capability of the aqueous extract to generate radical intermediates was observed at both high pH and near-neutral pH conditions. The findings suggest the antitumor bioactivities of TL against selected breast cancer cells may be due to induction of a G1 cell cycle arrest. Cytotoxicity and cell cycle perturbation that are associated with a high concentration of the extract could be in part explained by the total phenolic contents in the extract and the capacity to generate radical intermediates to modulate cellular proliferative signals.

Fast and reliable detection of toxic Crotalaria spectabilis Roth. in Thunbergia laurifolia Lindl. herbal products using DNA barcoding coupled with HRM analysis

Background

Nowadays, medicinal plants are used as a popular alternative to synthetic drugs. Many medicinal plant products have now been commercialized throughout various markets. These products are commonly sold in processed or modified forms such as powders, dried material and capsules, making it almost impossible to accurately identify the constituent species. The herbal plant known as ‘Rang Chuet’ in Thai has been widely used as remedies for various ailments. However, two medicinal plants species, Thunbergia laurifolia and Crotalaria spectabilis share this name. Duo to the similarity in nomenclature, the commercial products labeled as ‘Rang Chuet’ could be any of them. Recently, the evidence of hepatotoxic effects linked to use of C. spectabilis were reported and is now seriously concern. There is a need to find an approach that could help with species identification of these herbal products to ensure the safety and efficacy of the herbal drug.

Methods

Here DNA barcoding was used in combination with High Resolution Melting analysis (Bar-HRM) to authenticate T. laurifolia species. Four DNA barcodes including matK, rbcL, rpoC and trnL were selected for use in primers design for HRM analysis to produce standard melting profiles of the selected species. Commercial products labeled as ‘Rang Chuet’ were purchased from Thai markets and authentication by HRM analyses.

Results

Melting data from the HRM assay using the designed primers showed that the two ‘Rang Chuet’ species could easily be distinguished from each other. The melting profiles of the all four region amplicons of each species are clearly separated in all three replicates. The method was then applied to authenticate products in powdered form. HRM curves of all ten test samples indicated that three of the tested products did not only contain the T. laurifolia species.

Conclusion

The herbal drugs derived from different plants must be distinguished from each other even they share the same vernacular name. The Bar-HRM method developed here proved useful in the identification and authentication of herbal species in processed samples. In the future, species authentication through Bar-HRM could be used to promote consumer trust, as well as raising the quality of herbal products.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-015-0692-6) contains supplementary material, which is available to authorized users.

Ethnomedicinal plants used for digestive system disorders by the Karen of northern Thailand

BACKGROUND

Digestive system disorders have a substantial effect on worldwide morbidity and mortality rates, including in Thailand, where the majority of the rural areas have a lack of proper sanitation and awareness about disease prevention. This has led to the prevalence of different types of digestive diseases. Karen people in Thailand still use medicinal plants as first aid remedies in treating these diseases. Therefore, this study aimed at documenting the plants used to cure and prevent different types of digestive system disorders by Karen people of Chiang Mai Province, northern Thailand.

METHODS

Ethnomedicinal data were collected from six key informants and 172 non-specialist informants regarding their traditional knowledge of medicinal plants. Quantitative approaches were used to determine Use Value (UV), Informant Consensus Factor (ICF) and Fidelity Level (FL) values.

RESULTS

The study revealed that 36 medicinal plant species belonging to 31 genera and 24 families were used to treat digestive system disorders. The most prevalent plant families were Zingiberaceae (6 species), Euphorbiaceae (4 species) and Fabaceae (4 species). Leaves were the most commonly used plant part accounting for 32.6% of the plants, followed by the bark (18.6%). About 60% of the administrations were given orally by potion (60%) and consumption as food was also indicated (14%). The highest ICF values were recorded for carminative disorders, stomachaches, geographic tongue, constipation, appetite stimulants and food poisoning (1.00 each) indicating the best agreement among the informants knowledge of medicinal plants that were used to treat aliments in these categories. The highest fidelity level values were recorded for Punica granatum (100.00), Psidium guajava (95.45), and Gymnopetalum integrifolium (90.91) showing conformity of knowledge on species with the best healing potential.

CONCLUSION

Medicinal plants still play an important role among Karen culture. The present information on these medicinal plants, which have high UV and FL values, may serve as the baseline data to initiate further research for the discovery of new compounds and the biological activities of these potential plant remedies. Further research on these plants may provide some important clues for the development of new drugs for the treatment of digestive system diseases.

Protective effect of Thunbergia laurifolia extract on hemolysis during Plasmodium berghei infection

This study was aimed to investigate the efficacy of Thunbergia laurifolia leaf extract to protect hemolysis in mice infected with Plasmodium berghei. Aqueous leaf extract of T. laurifolia was freshly prepared, and total polyphenol was then measured using Folin-Ciocalteu reagent method. For in vivo test, ICR mice were given intraperitoneally with this extract (1,000 mg/kg) once a day for four consecutive days and subsequently inoculated with 1 × 10(6) parasitized erythrocytes of P. berghei ANKA by intraperitoneal injection for 8 days. The results showed that hemolysis was inhibited as indicated by %hematocrit (%Hct) which was normal in infected mice treated with T. laurifolia extract. Untreated and pyrimethamine-treated controls showed decreasing %Hct. Moreover, no any toxic signs were observed in normal mice treated with this extract. We conclude that T. laurifolia leaf extract clearly protects hemolysis during P. berghei infection in mice.

A combination of praziquantel and the traditional medicinal plant Thunbergia laurifolia on Opisthorchis viverrini infection and cholangiocarcinoma in a hamster model

Cholangiocarcinoma (CCA) associated by Opisthorchis viverrini remains a health problem in Southeast Asia including Thailand. At present, there is still no efficient treatment for CCA. Thunbergia laurifolia is a traditionally used medicinal plant; its aqueous leave extract possesses the antioxidant activity and anti-inflammatory on hamster opisthorchiasis had been reported previously. Here, we demonstrate the combined effects of the T. laurifolia extract plus antihelminthic drug, praziquantel (PZ) on hamsters with opisthorchiasis and hamsters with opisthorchiasis related-cholangiocarcinoma through light microscopic observations of histopathological changes, as well as liver function tests for alanine transaminase (ALT) and alkaline phosphatase, and kidney function tests for blood urea nitrogen and creatinine. Results showed T. laurifolia extract combined with praziquantel reduced inflammatory cell aggregation and inhibiting CCA development, which were correlated to the serum ALT level. These present studies suggest that administration of T. laurifolia after praziquantel treatment clearly improve the hepatobiliary system and could reduce the risk of subsequent CCA development in human.