Ethanolic extracts ofTinospora cordifoliaandAlstonia scholarisshow antimicrobial activity towards clinical isolates of methicillin-resistant and carbapenemase-producing bacteria

Indian herb Tinospora cordifolia and Tinospora species: Phytochemical and therapeutic application

Clinical investigations are increasingly focusing on natural materials with medical benefits because, in contrast to medicines, they have extremely few adverse effects. Tinospora species of the Menispermaceae family has many bioactive principles for plant nutraceuticals. A thorough assessment of the existing literature revealed that Indian Tinospora species are an important group of medicinal herbs used for a variety of pharmacological activities. While, Tinospora cordifolia is widely recognized as a significant herb in the Indian System of Medicines (ISM) due to its bioactive components and has been used in the treatment of diabetes, cancer, urinary problems, fever, jaundice, helminthiasis, leprosy, dysentery, skin diseases, and many more. Using the search phrases "phytochemistry," "traditional uses," and "pharmacological evaluation of Indian Tinospora species," appropriate articles were carefully extracted from the MEDLINE/PubMed, Scopus, and WOS databases. Around 180 articles, related to the India Tinospora species, were selected from a pool of 200 papers published between 1991 and 2023. T. cordifolia has received a lot of scientific attention because of its diverse therapeutic characteristics in treating various diseases. Our present study in this review encompasses 1.) Phytochemistry, traditional uses and pharmacological potential of T. cordifolia as well as other Indian Tinospora species. 2.) Safety and toxicity study and available marketed formulation of T. cordifolia for the treatment of various diseases. The chemical constitution and pharmacological characteristics of other Tinospora species must also be investigated, indicating a need for further scientific research.

Use of Essential Oils to Counteract the Phenomena of Antimicrobial Resistance in Livestock Species

Antimicrobial resistance is an increasingly widespread phenomenon that is of particular concern because of the possible consequences in the years to come. The dynamics leading to the resistance of microbial strains are diverse, but certainly include the incorrect use of veterinary drugs both in terms of dosage and timing of administration. Moreover, the drug is often administered in the absence of a diagnosis. Many active ingredients in pharmaceutical formulations are, therefore, losing their efficacy. In this situation, it is imperative to seek alternative treatment solutions. Essential oils are mixtures of compounds with different pharmacological properties. They have been shown to possess the antibacterial, anti-parasitic, antiviral, and regulatory properties of numerous metabolic processes. The abundance of molecules they contain makes it difficult for treated microbial species to develop pharmacological resistance. Given their natural origin, they are environmentally friendly and show little or no toxicity to higher animals. There are several published studies on the use of essential oils as antimicrobials, but the present literature has not been adequately summarized in a manuscript. This review aims to shed light on the results achieved by the scientific community regarding the use of essential oils to treat the main agents of bacterial infection of veterinary interest in livestock. The Google Scholar, PubMed, SciELO, and SCOPUS databases were used for the search and selection of studies. The manuscript aims to lay the foundations for a new strategy of veterinary drug use that is more environmentally friendly and less prone to the emergence of drug resistance phenomena.

Plants with Antimicrobial Activity Growing in Italy: A Pathogen-Driven Systematic Review for Green Veterinary Pharmacology Applications

Drug resistance threatening humans may be linked with antimicrobial and anthelmintic resistance in other species, especially among farm animals and, more in general, in the entire environment. From this perspective, Green Veterinary Pharmacology was proven successful for the control of parasites in small ruminants and for the control of other pests such as varroa in bee farming. As in anthelmintic resistance, antimicrobial resistance (AMR) represents one of the major challenges against the successful treatment of infectious diseases, and antimicrobials use in agriculture contributes to the spread of more AMR bacterial phenotypes, genes, and proteins. With this systematic review, we list Italian plants with documented antimicrobial activity against possible pathogenic microbes. Methods: The literature search included all the manuscripts published since 1990 in PubMed, Web of Science, and Scopus using the keywords (i) "antimicrobial, plants, Italy"; (ii) "antibacterial, plant, Italy"; (iii) "essential oil, antibacterial, Italy"; (iv) "essential oil, antimicrobial, Italy"; (v) "methanol extract, antibacterial, Italy"; (vi) "methanol extract, antimicrobial, Italy". Results: In total, 105 manuscripts that documented the inhibitory effect of plants growing in Italy against bacteria were included. One hundred thirty-five plants were recorded as effective against Gram+ bacteria, and 88 against Gram-. This will provide a ready-to-use comprehensive tool to be further tested against the indicated list of pathogens and will suggest new alternative strategies against bacterial pathogens to be employed in Green Veterinary Pharmacology applications.

Tinospora cordifolia (Willd.) Miers: Protection mechanisms and strategies against oxidative stress-related diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Tinospora cordifolia (Willd.) Miers (Menispermaceae) is a Mediterranean herb, used in Ayurvedic, Siddha, Unani, and folk medicines. The herb is also used in conventional medicine to treat oxidative stress-related diseases and conditions, including inflammation, pain, diarrhea, asthma, respiratory infections, cancer, diabetes, and gastrointestinal disorders.

AIM OF THE REVIEW

The taxonomy, botanical classification, geographical distribution, and ethnobotanical uses of T. cordifolia, as well as the phytochemical compounds found in the herb, the toxicology of and pharmacological and clinical studies on the effects of T. cordifolia are all covered in this study.

MATERIALS AND METHODS

To gather information on T. cordifolia, we used a variety of scientific databases, including Scopus, Google Scholar, PubMed, and Science Direct. The information discussed focuses on biologically active compounds found in T. cordifolia, and common applications and pharmacological activity of the herb, as well as toxicological and clinical studies on its properties.

RESULTS

The findings of this study reveal a connection between the use of T. cordifolia in conventional medicine and its antioxidant, anti-inflammatory, antihypertensive, antidiabetic, anticancer, immunomodulatory, and other biological effects. The entire plant, stem, leaves, root, and extracts of T. cordifolia have been shown to have a variety of biological activities, including antioxidant, antimicrobial, antiviral, antiparasitic, antidiabetic, anticancer, anti-inflammatory, analgesic and antipyretic, hepatoprotective, and cardioprotective impact. Toxicological testing demonstrated that this plant may have medicinal applications. T. cordifolia contains a variety of biologically active compounds from various chemical classes, including alkaloids, terpenoids, sitosterols, flavonoids, and phenolic acids. Based on the reports researched for this review, we believe that chemicals in T. cordifolia may activate Nrf2, which leads to the overexpression of antioxidant enzymes such as CAT, GPx, GST, and GR, and thereby induces the adaptive response to oxidative stress. T. cordifolia is also able to reduce NF-κB signalling by inhibiting PI3K/Akt, activating AMPK and sirtuins, and downregulating PI3K/Akt.

CONCLUSIONS

Our findings indicate that the pharmacological properties displayed by T. cordifolia back up its conventional uses. Antimicrobial, antiviral, antioxidant, anticancer, anti-inflammatory, antimutagenic, antidiabetic, nephroprotective, gastroprotective, hepatoprotective, and cardioprotective activities were all demonstrated in T. cordifolia stem extracts. To validate pharmacodynamic targets, further research is needed to evaluate the molecular mechanisms of the known compounds against gastrointestinal diseases, inflammatory processes, and microbial infections, as immunostimulants, and in chemotherapy. The T. cordifolia safety profile was confirmed in a toxicological analysis, which prompted pharmacokinetic assessment testing to confirm its bioavailability.

Tinospora Cordifolia: A review of its immunomodulatory properties

Emergent health threats have heightened human awareness of the need for health and wellness measures that promote resilience to disease. In addition to proper nutrition and exercise, health-conscious consumers are seeking natural-based modalities, e.g. botanical preparations, that positively impact the immune system. In Ayurvedic ethnomedicine, Tinospora cordifolia (T. cordifolia), a deciduous climbing shrub indigenous to India, has been used to historically to combat acute and chronic inflammation as well as to promote a balanced immune response. As a dietary supplement, T. cordifolia has been administered most often as a decoction either alone or in compositions containing other medicinal plant extracts of the Terminalia and Phyllanthus species. Extensive phytochemical characterization of aqueous and alcoholic extracts of different Tinospora species has identified over two hundred different phytochemicals from non-overlapping chemical classes with the most abundant being diterpenoids containing the clerodane-type skeleton. Numerous pharmacology studies have demonstrated that T. cordifolia modulates key signaling pathways related to cell proliferation, inflammation, and immunomodulation. However, rigorous dereplication studies to identify active constituents in various T. cordifolia extracts and their fractions are lacking. In this review, we will summarize the current information regarding T. cordifolia's ethnomedicinal uses, phytochemistry, pharmacological activities, and safety in order to highlight its potential as an immunomodulatory dietary supplement.

Synergistic effects of anti-MRSA herbal extracts combined with antibiotics

MRSA is a super drug-resistant bacterium. Developing new drug or therapeutic strategies against MRSA is urgently needed. Increasing evidence has shown that herbal extracts and antibiotics can have synergistic effects against MRSA. This review focuses on commonly used antibiotics combined with herbal extracts against MRSA and the corresponding mechanisms. Through systematic analysis, we found that herbal extracts combined with antibiotics, such as β-lactams, quinolones, aminoglycosides, tetracyclines and glycopeptides, could greatly enhance the antibacterial effects of the antibiotics, reduce the dosage and toxic side effects, and reverse MRSA resistance. Therefore, we conclude that herbal extracts combined with antibiotics may be a promising strategy to combat MRSA. This review provides a novel idea for overcoming antibiotic resistance.

Genus Tinospora: Ethnopharmacology, Phytochemistry, and Pharmacology

The genus Tinospora includes 34 species, in which several herbs were used as traditional medicines by indigenous groups throughout the tropical and subtropical parts of Asia, Africa, and Australia. The extensive literature survey revealed Tinospora species to be a group of important medicinal plants used for the ethnomedical treatment of colds, headaches, pharyngitis, fever, diarrhea, oral ulcer, diabetes, digestive disorder, and rheumatoid arthritis. Indian ethnopharmacological data points to the therapeutic potential of the T. cordifolia for the treatment of diabetic conditions. While Tinospora species are confusing in individual ingredients and their mechanisms of action, the ethnopharmacological history of those plants indicated that they exhibit antidiabetic, antioxidation, antitumor, anti-inflammation, antimicrobial, antiosteoporosis, and immunostimulation activities. While the clinical applications in modern medicine are lacking convincing evidence and support, this review is aimed at summarizing the current knowledge of the traditional uses, phytochemistry, biological activities, and toxicities of the genus Tinospora to reveal its therapeutic potentials and gaps, offering opportunities for future researches.

Acute and Sub-Acute Toxicity Evaluation of the Methanolic Extract of Alstonia scholaris Stem Bark

Alstonia scholaris has been used by traditional medicine practitioners since the medieval ages for the treatment of diseases. The aim of this research was to evaluate the acute and sub-acute oral toxicity of its methanolic extract. The acute toxicity test was conducted using Sprague Dawley (SD) rats. The methanolic extract of Alstonia scholaris stem bark (ASME) was administrated in a single dose of 2000 mg/kg via oral gavage; and the animals were observed for any behavioral changes or mortality. In the sub-acute toxicity study, SD rats received three doses of ASME (250, 500 and 1000 mg/kg) for 28 days via oral gavage. During these 28 days of treatment, the rats were observed weekly for toxicity symptoms. Following the 28-day treatment, the rats were sacrificed for hematological, biochemical and histopathology studies. In the acute toxicity study, Alstonia scholaris was found to be non-toxic at a dose of 2000 mg/kg b.w. In the sub-acute toxicity study, significant variations in body weight, hematological and biochemical parameters were observed in the experimental groups at the dose of 500 and 1000 mg/kg with the death of two female rats being recorded at the highest dose (1000 mg/kg b.w.). Histopathological studies revealed slight degeneration (lesion) and centrilobular necrosis in the liver, which was most expressed in the highest-dose group. These results demonstrate that, while a single dose and short term oral intake of Alstonia scholaris bark extract caused no toxicity up to a dose of 2000 mg/kg b.w., toxic effects manifested in the long term treatment at the highest dose (500 and 1000 mg/kg). The long-term toxic effect was found to be associated with alterations in hematological compositions and end-organ damage to the liver. Thus, prolonged use of high doses of ASME orally should be discouraged and lower doses encouraged.

Antibacterial and Synergistic Activity of Pentacyclic Triterpenoids Isolated from Alstonia scholaris

(1) Background: Alstonia scholaris (Apocynaceae) is an important medicinal plant that has been historically used in “Dai” ethnopharmacy to treat infectious diseases in China. Although various pharmacological activities have been reported, the antimicrobial constitutes of A. scholaris have not yet been identified. The objective of this study is to evaluate the antibacterial constitutes from the leaf extract of A. scholaris and to assess the synergistic effects of isolated compounds with antibiotics against bacterial pathogens.; (2) Methods: The chemical constitutes isolated from the leaf extract of A. scholaris were structurally identified by NMR. The antibacterial and synergistic effect of compounds was assessed by calculating the minimal inhibitory concentration (MIC), checkerboard dilution test, and time-kill assay.; (3) Results: Six pentacyclic triterpenoids were structurally identified as (1) lupeol, (2) betulin, (3) 3-hydroxy-11-ursen-28,13-olide, (4) betulinic acid, (5) oleanolic acid and (6) ursolic acid. Both oleanolic and ursolic acid showed antibacterial activity but were limited to Gram-positive bacteria. Ursolic acid showed a synergistic effect with ampicillin and tetracycline against both Bacillus cereus and S. aureus.; (4) Conclusion: These findings reflect that pentacyclic triterpenoids are the antibacterial chemicals in A. scholaris. The ability of ursolic acid to enhance the activity of antibiotics can constitute a valuable group of therapeutic agents in the future.

Mechanisms underlying the antihypertensive effect of Alstonia scholaris

ETHNOPHARMACOLOGICAL RELEVANCE

Alstonia scholaris has a long history of use in the Ayurveda traditional treatment of various ailments including hypertension. We have reported the blood pressure lowering activity of the extract of A. scholaris. The following research aim to delineate the pharmacological mechanism involve in the antihypertensive action.

MATERIALS AND METHOD

Vasorelaxant effect of the n-butanol fraction of A. scholaris (NBF-ASME) was evaluated on rat aorta pre-contracted with phenyelphrine (PE, 1 µM). Aortic rings preparation were pre-incubated with various antagonists like 1H-[1,2,4] oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ 10 μM), methylene blue (MB 10 μM), Nω-nitro-L-arginine methyl ester hydrochloride (l-NAME 10 μM), atropine (10 μM), indomethacin (1 μM), ML-9 and various K(+) channel blockers such as glibenclamide (10 μM) and tetraethyl ammonium (TEA 10 μM) for mechanism study.

RESULT

The results showed that pre-incubation of aortic rings with the extract (0.5, 1 and 2mg/mL) significantly inhibit the contractile response of the rings to phenylephrine-induced contraction (p<0.05-0.001). Removal of endothelium, incubation with L-NAME, indomethacin, atropine and propranolol did not significantly affect the relaxation effect of NBF-ASME. Furthermore, the K(+) channel blockers, TEA and glibenclamide showed no inhibitory effect. However, aortic rings pretreated with ODQ and ML-9 showed a significant suppression of the relaxation curve of NBF-ASME (p<0.01-0.001). In Ca(2+)-free solution, NBF-ASME inhibits the release of intracellular Ca(2+) from the sarcoplasmic reticulum. NBF-ASME also inhibits calcium chloride (CaCl2)-induced contraction in endothelium-denuded aortic rings.

CONCLUSION

The results from this study suggests that A. scholaris exerts vasodilation via calcium channels blockade, direct activation of soluble guanylate cyclase and possibly by also inhibiting the formation of inositol 1, 4, 5-triphosphate.