Probing PXR activation and modulation of CYP3A4 by Tinospora crispa and Tinospora sinensis

ETHNOPHARMACOLOGICAL RELEVANCE

The two Tinospora species, T. crispa and T. sinensis, native to Southeast Asia, are integral components of various traditional preparations with structure-function claims to treat various disorders, including diabetes and inflammation.

AIM OF THE STUDY

To assure the safety of the botanicals finished products, herb-drug interaction potential of T. crispa and T. sinensis was investigated by testing their extracts and compounds for in vitro activation of the pregnane X-receptor (PXR) and the modulation of CYP3A4 isozyme, selectively.

MATERIALS AND METHODS

A total of sixteen fully characterized phytochemicals from T. crispa and T. sinensis were evaluated for PXR activation by luciferase reporter gene assay. CYP3A4 inhibition studies were carried out for eleven compounds. In addition, docking studies were performed to elucidate the possible binding modes to the PXR by the compounds using computational methods.

RESULTS

Significant activation of PXR (2-fold) was observed for both extracts and non-polar fractions of T. crispa. Among the pure compounds, columbin showed highest activation of PXR (3-fold), which was comparable with the positive control, rifampicin. Vital interactions were predicted with docking simulation of PXR-columbin complex with critical amino acid residues (Trp-299) that are known for the activation of PXR. The methanolic extracts of T. crispa and T. sinensis also showed considerable CYP3A4 inhibition.

CONCLUSION

T. crispa and T. sinensis, both demonstrated the potential to mediate herb-drug interaction through PXR activation and inhibition of CYP3A4 isozyme. Moreover, the elucidation of the potential to induce herb-drug interaction, by the phytochemicals of these Tinospora plants, thereby supports the need for further investigation to establish the clinical relevancy of these constituents for possible adverse interactions with pharmaceutical drugs.

Forest Fevers: traditional treatment of malaria in the southern lowlands of Laos

ETHNOPHARMACOLOGICAL RELEVANCE

Malaria is still a highly challenging public health issue in southern Lao PDR, with increasing cases of artemisinin resistance and Plasmodium vivax infections which are more complicated to treat. Traditional medicine has a long history of use in Laos, and is primarily practised by traditional village healers, who possess unique bodies of transmitted knowledge focused on herbal prescriptions, including those for the treatment of malaria. Villagers also use plants for healthcare in the home. The aim of the study is to document local fever concepts and use of herbal remedies, and examine whether they may have potential as complementary treatments against malaria.

MATERIALS AND METHODS

The study took place in Champasak province in the far south of Laos, in primarily lowland areas. First, 35 traditional healers across the 10 districts of the province were interviewed to elicit details about knowledge and treatment of fevers. Second, a household survey was conducted in a village in a malaria-endemic area; 97 households were interviewed on fever incidence, differentiation, treatment-seeking behaviour and knowledge of plant-based remedies for fevers. Plants indicated by both healers and villagers were collected and voucher specimens deposited in the herbarium of the National University of Laos for identification.

RESULTS

Malaria is a well-known pathology among the healers and villagers of lowland Champasak province; biomedical treatments are preferentially used, but traditional medicine is a popular complementary method, especially in chronic cases with additional symptoms. 30 different fever types were recorded, which were usually named symptomatically, and grouped into 12 categories. Some were described as forms of malaria, which was conceived as a dynamic, changing pathology affecting many body systems. Healers formulate treatments based on symptoms and the person's constitution, and with the intention of creating specific pharmacological actions associated with temperature or flavours. 11 of the healers gave prescriptions for malaria (27 in total), including 47 identified plant species. The most-used plants (4 or more use-reports) were also the most cited in the literature for use against malaria, demonstrating a correspondence between Lao healers and other traditional medical systems. Furthermore, some of these species show promising results for future research, especially Amorphophallus paeniifolius (Dennst.) Nicolson and Alocasia macrorrhizos (L.) G. Don.

CONCLUSION

Traditional healers are important actors in the treatment of malaria in southern Laos, and herbal remedies should be evaluated further by the use of reverse treatment outcome trials, especially those which may be of use as complementary remedies in treating P. vivax. Initiatives on knowledge transmission, medicinal plant conservation and healthcare integration are also urgently needed.

Antipyretic and hepatoprotective potential of Tinospora crispa and investigation of possible lead compounds through in silico approaches

This research describes an investigation of the antipyretic and hepatoprotective properties of both a crude organic extract and various subfractions of the ethnomedicinal plant Tinospora crispa, using appropriate animal models. In an attempt to identify potential lead hepatoprotective compounds, in silico experiments were utilized. Antipyretic activity was assessed via the Brewer's yeast-induced pyrexia method, while hepatoprotective effects were evaluated in a carbon tetrachloride (CCl4)-induced animal model. A computer-aided prediction of activity spectra for substances (PASS) model was applied to a selection of documented phytoconstituents, with the aim of identifying those compounds with most promising hepatoprotective effects. Results were analyzed using Molinspiration software. Our results showed that both the methanol extract (METC) and various subfractions (pet ether, PEFTC; n-hexane, NHFTC; and chloroform, CFTC) significantly (p < .05) reduced pyrexia in a dose-dependent manner. In CCl4-induced hepatotoxicity studies, METC ameliorated elevated hepatic markers including serum alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP), and total bilirubin. Malondialdehyde (MDA) levels were significantly reduced, while superoxide dismutase (SOD) levels were significantly increased. Among a selection of metabolites of T. crispa, genkwanin was found to be the most potent hepatoprotective constituent using PASS predictive models. These results demonstrate that both the methanolic extract of T. crispa and those fractions containing genkwanin may offer promise in reducing pyrexia and as a source of potential hepatoprotective agents.

Development of a chemical fingerprint as a tool to distinguish closely related Tinospora species and quantitation of marker compounds

Tinospora species are morphologically similar. Several cases of human toxicity have been reported in association with T. crispa. A chemical fingerprint was developed to differentiate T. crispa from its closely related species and to quantitate its major furanoditerpenes namely as borapetosides B, C and F. The rapid, sensitive and repeatable method was established using ultra-high performance liquid chromatography coupled with photodiode array and single quadrupole electrospray mass spectrometry detectors using a flavonoid, two alkaloids, an amide and six diterpenoids. Qualitative and quantitative determination was performed by UHPLC-UV and confirmed by MS. The intra-day RSD for replicates was between 0.9 and 6.8% and inter-day RSD was between 1.2 and 9.1%. Recovery was 97-103 %. The method is useful to achieve decisiveness in not only identifying but also differentiating T. crispa from T. sinensis and other closely related Tinospora species. Seventeen Tinospora plant samples and seventeen dietary supplements claiming T. crispa, T. sinensis and T. cordifolia were analyzed. The newly developed and validated method successfully resulted in the conclusive identification of two dietary supplements to be mislabeled.

Will every child have allergic rhinitis soon?

OBJECTIVES

Given the increasing prevalence of AR amongst children, we aimed to review the literature regarding the future of AR in this population.

METHODS

We searched the PubMed, Google and Proquest Central databases at Kırıkkale University Library. Search terms used were: "allergic rhinitis", "children", "paediatric", "allergy", "future", "risk factors", "treatment", "pharmacotherapy" and/or "allergen - specific immunotherapy". With regard to risk factors for allergic rhinitis, the terms "Environmental factors", "Improved hygiene", "Increased indoor allergen exposure", "Farms, villages, worms, and other parasites", "Environmental toxicants", "Diet", "Lifestyle changes", "Air pollution" and "Climate factors" were searched for. "Prevention of allergic diseases" and "Allergen-specific immunotherapy in the future" were also included in the search.

RESULTS

AR has a high prevalence and causes considerable morbidity, has associated comorbidity and features specific complications. The principal treatments rely on avoiding the allergens responsible, and administering drug treatment or immunotherapy, which targets specific antigens. Genetic drift does not explain the rising prevalence of allergic disorders, but multifactorial environmental factors are likely culprits. Amongst such environmental factors to consider are the rise in caesarean births, decreases in breast feeding, dietary changes resulting in less fresh produce being consumed, the eradication of intestinal worm infestations, alterations in the way homes are aired and heated, children taking less exercise and being outdoors for shorter periods, whilst also having more contact with pollution.

CONCLUSION

Barring substantial lifestyle alterations, more and more children are likely to develop AR. It may prove feasible to stop allergy developing in the first place through manipulation of the microbiome, but the exact format such a modification should involve remains to be discovered. Molecular allergological techniques do offer the prospect of more precisely targeted immunotherapy, the sole disease modifier at present. However, at present the complexity and cost of such interventions prevents their widespread use and research in this area is still needed. The majority of children with AR are going to be managed using nasal saline sprays, since they are the most straightforward and least risky alternative for first line treatment.

Literature review of liver injury induced by Tinospora crispa associated with two cases of acute fulminant hepatitis

INTRODUCTION

Species of Tinospora are used as herbal remedies for the treatment of various diseases with very few toxic effects having been reported. Tinospora cordifolia (TCF) has been reported to effectively prevent hepatotoxicity. However, there are an increasing number of cases revealing that Tinospora crispa (TCP) might have the negative effect of inducing hepatotoxicity. Because of the similar leaves, people may mistake TCP for TCF, and consume it with the purpose of protecting liver function.

OBJECTIVE

Find out the misusing level of TCP and TCF and which chemical compound in TCP might induce hepatotoxicity.

METHODS

We report two cases of acute fulminant hepatitis associated with chronic use of TCP. Given that the two herbs were misidentified in these two reports, we investigated the frequency of erroneous identification by using three keywords ("Guduchi", "Tinospora cordifolia", "Tinospora crispa") to search images from the Google Images database. To further clarify the influence of liver function between TCP and TCF, we searched PubMed (up to 29 July 2018) for relevant publications on clinical trials or case reports.

RESULTS

Based on web review, over 35 percent of websites failed to accurately identify these two herbs. The different effects on liver function between TCP and TCF were compared through literature review. It indicated that TCF exerted liver protection, TCP had a contrary effect, suggesting its cis-Clerodane-type furano-diterpenoids might be an important factor of inducing hepatotoxicity.

CONCLUSIONS

We concluded that people might cause hepatic injury or even death without correctly identifying these two Tinospora species.

Hypoglycemia induced by Plasmodium berghei infection is prevented by treatment with Tinospora crispa stem extract

During Plasmodium malaria parasite infection in a human, the intraerythrocytic stages lead to the clinical manifestations of the disease, especially hypoglycemia. Hypoglycemia is a recognized feature of severe malaria and linked with a high risk of mortality for children. Hence, the present study aimed to investigate the protective effect of T. crispa stem extract on hypoglycemia induced by P. berghei infection tested with a mouse model. ICR mice were inoculated with 1 × 10⁷ parasitized erythrocytes of P. berghei ANKA (PbANKA) by intraperitoneal injection and given 50, 100, and 200 mg/kg of ethanolic extract for 4-consecutive days. The results showed that T. crispa stem extract exerted a protective effect (100%) on hypoglycemia induced by PbANKA infection at doses of 100 and 200 mg/kg. A significantly (p < .05) prolonged mean survival time (28.0 ± 1.9 days) of the extract treated mice was also observed. Additionally, no effect on blood glucose levels was seen in normal mice treated with all doses of extract. It can be concluded that T. crispa stem extract may have beneficial properties in protecting against hypoglycemia, and in increasing survival time during malaria infection.

Clerodane furanoditerpenoids as the probable cause of toxic hepatitis induced by Tinospora crispa

Tinospora crispa is a popular traditional herbal plant commonly used throughout the world for treatment of various diseases, in particular type 2 diabetes mellitus. We report here a new case of toxic hepatitis in a 57-year old male patient in the French West Indies following the consumption of two aqueous extracts of fresh Tinospora crispa stems. It thus differs from two previously reported cases that concerned the chronic intake of powdered dry stems delivered in solid oral dosage forms (i.e. pellets and tablets). Liquid Chromatography-Diode Array Detection-Mass Spectrometry (LC/DAD/MS) analyses were performed on an aqueous extract of the offending sample that mimics the swallowed preparation. They revealed the presence of species-specific molecular marker borapetoside C (1) and thus enabled an unambiguous phytochemical identification. The exploration of tandem MS/MS data obtained by ultra-high performance liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry (UHPLC-ESI-QTOF-HRMS) allowed the identification of 17 additional cis-clerodane-type furanoditerpenoid lactones, analogues of 1. These results support the hypothesis that the mechanisms underlying hepatotoxicity of Tinospora crispa are the same as those encountered with furanoditerpenoids-containing plants such as Teucrium chamaedrys or Dioscorea bulbifera. In the context of type 2 diabetes treatment, we recommend that Tinospora crispa intake should be more closely monitored for signs of hepatotoxicity.

Tinospora crispa (L.) Hook. f. & Thomson: A Review of Its Ethnobotanical, Phytochemical, and Pharmacological Aspects

Tinospora crispa (L.) Hook. f. & Thomson (Menispermaceae), found in the rainforests or mixed deciduous forests in Asia and Africa, is used in traditional medicines to treat numerous health conditions. This review summarizes the up-to-date reports about the ethnobotany, phytochemistry, pharmacological activities, toxicology, and clinical trials of the plant. It also provides critical assessment about the present knowledge of the plant which could contribute toward improving its prospect as a source of lead molecules for drug discovery. The plant has been used traditionally in the treatment of jaundice, rheumatism, urinary disorders, fever, malaria, diabetes, internal inflammation, fracture, scabies, hypertension, reducing thirst, increasing appetite, cooling down the body temperature, and maintaining good health. Phytochemical analyses of T. crispa revealed the presence of alkaloids, flavonoids, and flavone glycosides, triterpenes, diterpenes and diterpene glycosides, cis clerodane-type furanoditerpenoids, lactones, sterols, lignans, and nucleosides. Studies showed that the crude extracts and isolated compounds of T. crispa possessed a broad range of pharmacological activities such as anti-inflammatory, antioxidant, immunomodulatory, cytotoxic, antimalarial, cardioprotective, and anti-diabetic activities. Most pharmacological studies were based on crude extracts of the plant and the bioactive compounds responsible for the bioactivities have not been well identified. Further investigations are required to transform the experience-based claims on the use of T. crispa in traditional medicine practices into evidence-based information. The plant extract used in pharmacological and biological studies should be qualitatively and quantitatively analyzed based on its biomarkers. There should be detail in vitro and in vivo studies on the mechanisms of action of the pure bioactive compounds and more elaborate toxicity study to ensure safety of the plant for human use. More clinical trials are encouraged to be carried out if there are sufficient preclinical and safety data.

Toxic hepatitis induced by a herbal medicine: Tinospora crispa

Herbal remedies are becoming increasingly popular in many countries. Tinospora species (Menispermaceae) is commonly used as a herbal medicine in South Asia, but very few toxic effects have been described. We report a case of acute hepatitis associated with chronic use of high doses of Tinospora crispa. A 49-year-old male with chronic low back pain bought a herbal medicine at a market in Vietnam that was supposed to be Tinospora crispa, and started to take 10 pellets per day. He had no medical history and did not take any other drugs or toxins. Four weeks later; he developed dark urine and pale stools, associated with asthenia and right hypochondrial pain. Two months after starting treatment, he was referred to the hepatology department with jaundice. Blood tests showed aspartate aminotransferase: 1.169 IU/l, alanine aminotransferase: 2.029 IU/l, total bilirubin: 20.47 mg/dl, direct bilirubin: 13.29 mg/dl, and γ-glutamyltransferase: 243 IU/l. Viral and autoimmune hepatitis were eliminated. Upper abdominal ultrasound was normal. Histopathological findings were consistent with a toxic reaction. The herbal medicine was stopped on admission and the patient fully recovered without treatment, with normal liver function 2 months after the acute episode. Tinospora crispa was clearly identified in the pellets by microscopic analysis of the botanical characters combined with chromatographic fingerprints. The use of herbal medicines containing Tinospora crispa can induce toxic hepatitis. Recovery can be complete after discontinuation. This case highlights the risk associated with traditional herbal remedies.