Short-term treatment with Uncaria tomentosa aggravates the injury phenotype in mdx mice

Introduction: Uncaria tomentosa (Willd. ex Roem. & Schult.) DC. (Rubiaceae) or UT is a medicinal plant with antiviral, antimutagenic, anti-inflammatory and antioxidant properties. Duchenne muscular dystrophy (DMD) is a severe muscle wasting disease caused by mutations in the dystrophin gene; this deficiency leads to sarcolemma instability, inflammation, muscle degeneration and fibrosis. Objective: Considering the importance of inflammation to dystrophy progression and the anti-inflammatory activity of UT, in the present study we evaluated whether oral administration of UT extract would ameliorate dystrophy in the mdx mice, a DMD model. Methods: Eight-week-old male mdx mice were submitted to 200 mg/kg body weight daily UT oral administration for 6 weeks. General histopathology was analysed, and muscle tumor necrosis factor α, transforming growth factor-ß, myostatin and osteopontin transcript levels were assessed. The ability of mice to sustain limb tension to oppose their gravitational force was measured. Data were analysed with the unpaired Student's t-test. Results: Morphologically, both untreated and UT-treated animals exhibited internalised nuclei, increased endomysial connective tissue and variations in muscle fibre diameters. Body weight and muscle strength were significantly reduced in the UT-treated animals. Blood creatine kinase was higher in UT-treated compared to untreated animals. In tibialis anterior, myostatin, transcript was more highly expressed in the UT-treated while in the diaphragm muscle, transforming growth factor-ß transcripts were less expressed in the UT-treated. Conclusion: While previous studies identified anti-inflammatory, antiproliferative and anticarcinogenic UT effects, the extract indicates worsening of dystrophic muscles phenotype after short-term treatment in mdx mice.

Antiviral and Virucidal Activities of Uncaria tomentosa (Cat's Claw) against the Chikungunya Virus.

Uncaria tomentosa (UT) is a medicinal plant popularly known as cat's claw belonging to the Rubiaceae family that has been reported to display antiviral and anti-inflammatory activities. The chikungunya virus (CHIKV) outbreaks constitute a Brazilian public health concern. CHIKV infection develops an abrupt onset of fever, usually accompanied by a skin rash, besides incapacitating polyarthralgia. There is no vaccine available or treatment for CHIKV infection. The present study evaluates the hydroalcoholic extract of UT bark as a potential antiviral against CHIKV. The in vitro antiviral activity of the UT extract against the Brazilian CHIKV strain was assessed using quantitative reverse transcription polymerase chain reaction, flow cytometry, and plaque assay. Results obtained demonstrated that UT inhibits CHIKV infection in a dose-dependent manner. At the non-cytotoxic concentration of 100 µg/mL, UT exhibited antiviral activity above 90% as determined by plaque reduction assay, and it reduced the viral cytopathic effect. Similarly, a significant virucidal effect of 100 µg/mL UT was observed after 24 and 48 h post-infection. This is the first report on the antiviral activity of UT against CHIKV infection, and the data presented here suggests UT as a potential antiviral to treat CHIKV infection.

Comprehensive In Silico Analysis of Uncaria Tomentosa Extract: Chemical Profiling, Antioxidant Assessment, and CLASP Protein Interaction for Drug Design in Neurodegenerative Diseases.

BACKGROUND: Uncaria tomentosa is a traditional medicinal herb renowned for its anti-inflammatory, antioxidant, and immune-enhancing properties. In the realm of neurodegenerative diseases (NDDS), CLASP proteins, responsible for regulating microtubule dynamics in neurons, have emerged as critical players. Dysregulation of CLASP proteins is associated with NDDS, such as Alzheimer's, Parkinson's, and Huntington's diseases. Consequently, comprehending the role of CLASP proteins in NDDS holds promise for the development of innovative therapeutic interventions. OBJECTIVES: The objectives of the research were to identify phytoconstituents in the hydroalcoholic extract of Uncaria tomentosa (HEUT), to evaluate its antioxidant potential through in vitro free radical scavenging assays and to explore its potential interaction with CLASP using in silico molecular docking studies. METHODS: HPLC and LC-MS techniques were used to identify and quantify phytochemicals in HEUT. The antioxidant potential was assessed through DPPH, ferric reducing antioxidant power (FRAP), nitric oxide (NO) and superoxide (SO) free radical scavenging methods. Interactions between conventional quinovic acid, chlorogenic acid, epicatechin, corynoxeine, rhynchophylline and syringic acid and CLASP were studied through in silico molecular docking using Auto Dock 4.2. RESULTS: The HEUT extract demonstrated the highest concentration of quinovic acid derivatives. HEUT exhibited strong free radical-scavenging activity with IC50 values of 0.113 µg/ml (DPPH) and 9.51 µM (FRAP). It also suppressed NO production by 47.1 ± 0.37% at 40 µg/ml and inhibited 77.3 ± 0.69% of SO generation. Additionally, molecular docking revealed the potential interaction of quinovic acid with CLASP for NDDS. CONCLUSION: The strong antioxidant potential of HEUT and the interaction of quinovic acid with CLASP protein suggest a promising role in treating NDDS linked to CLASP protein dysregulation.

Effect of Uncaria tomentosa aqueous extract on the response to palmitate-induced lipotoxicity in cultured skeletal muscle cells.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is frequently associated with dyslipidemia, which corresponds to the increase in the triglycerides and fatty acid concentrations in tissues, such as the skeletal muscle. Also, T2DM molecular mechanism involves increasing in reactive oxygen species (ROS) production and oxidative stress. The use of herbal medicines such as Uncaria tomentosa (Ut) has been proposed as an auxiliary treatment for patients with T2DM. In this study, it was evaluated the effect of Ut aqueous extract on cell viability and ROS production, in skeletal myoblasts from C2C12 lineage exposed to the free fatty acid palmitate (PA). METHODS: Cells were incubated with PA in different concentrations ranging from 10 to 1000 µM, for 24 or 48 h, for cytotoxicity assay. Cell death, DNA fragmentation and ROS production assays were performed in cell cultures incubated with PA for 24 h, in the pre (preventive condition) or post treatment (therapeutic condition) with 250 µg/ml Ut aqueous extract, for 2 or 6 h. Cell death was evaluated by MTT method or flow cytometry. ROS generation was measured by fluorescence spectroscopy using the DCFDA probe. RESULTS: Cell viability was reduced to approximately 44% after the incubation with PA for 24 h from the concentration of 500 µM. In the incubation of cells with 500 µM PA and Ut extract for 6 h, in both conditions (preventive or therapeutic), it was observed an increase of 27 and 70% in cell viability respectively, in comparison to the cultures incubated with only PA. Also, the incubation of cultures with 500 µM PA, for 24 h, increased 20-fold the ROS formation, while the treatment with Ut extract, for 6 h, both in the preventive or therapeutic conditions, promoted decrease of 21 and 55%, respectively. CONCLUSION: The Ut extract was efficient in promoting cell protection against PA lipotoxicity and ROS generation, potentially preventing oxidative stress in C2C12 skeletal muscle cells. Since T2DM molecular mechanism involves oxidative stress condition and it is often associated with dyslipidemia and fatty acid accumulation in muscle tissue, these results open perspectives for the use of Ut as an auxiliary strategy for T2DM management.

Development, optimization, and invitro evaluation of novel fast dissolving oral films (FDOF's) of Uncaria tomentosa extract to treat osteoarthritis.

Fast dissolving oral films(FDOF's) are the popular dosage forms when placed in the oral cavity, disintegrate rapidly and dissolve to release the medication for improving oral absorption. Traditionally Uncaria tomentosa plant is used in the treatment of rheumatoid arthritis as Non-steroidal Anti-inflammatory agent along with analgesic properties. The plant extract is reported to be used in low dose as analgesic and anti-inflammatory agent in Rheumatoid Arthritis. No scientific data was reported on Uncaria plant formulation as FDOF's for treating osteoarthritis. This study aims to formulate fast oral dissolving film(FDOFs) Uncaria tomentosa bark extract and evaluate using Invitro studies for osteoarthritis. About 14 formulations were prepared using standard Box Behnken design protocol for optimization using the natural film formers, synthetic polymers, super disintegrants, plasticizers as independent variables with folding endurance and disintegration time as dependent variables by solvent casting method. Further the formulation characteristics including physical and mechanical behavior of films and drug release behavior was evaluated. The 3D countour plots and response curves suing the design expert software were investigated which proved that the optimized oral dissolving films of extract with Pullalan gum, HPMC (polymers), Propylene glycol, PEG 400 (Co-solvents) and Croscarmellose sodium (super Disintegrant) are stable and uniform with formulation characteristics. The drug release rates prove that F5 and F13 formulations showed 99.90% drug release within 30 min following first order kinetics with satisfactory mechanical properties. The study results suggest that the fast dissolving oral films of Uncaria tomentosa extract is novel, attractive and alternative to the available marketed products resulting in improved patient adherence in treatment of osteoarthritis.

Uncária Tomentosa (Wild.) D.C. em processos inflamatórios na doença de Alzheimer / Uncária Tomentosa (Wild.) D.C. en procesos inflamatorios en la enfermedad de Alzheimer / Uncária Tomentosa (Wild.) D.C. in inflammatory processes in Alzheimer's disease

Objetivo: explorar os mecanismos envolvidos no desencadeamento e progressão da Doença de Alzheimer (DA) de forma a embasar a sugestão da planta Uncaria Tomentosa (Wild.) como mais uma possiblidade terapêutica coadjuvante para prevenção e tratamento da DA. Método: Trata-se de uma revisão narrativa da literatura realizada com busca de artigos publicados em bases indexadas e diretamente nas revistas de interesse, utilizando-se como descritores "Uncária Tomentosa", "Doença de Alzheimer", e os respectivos termos em inglês. Resultados: com os avanços para a compreensão dos mecanismos moleculares que desencadeiam os efeitos apresentados no desenvolvimento da DA, os diversos mecanismos dos fitocompostos presentes na planta sugerem sua utilização como neuroprotetor, por mecanismos anti-inflamatórios, imunomoduladores e antioxidantes, cujas evidências em literatura são apresentadas para defesa de sua utilização nesta patologia. Conclusão: foram encontradas evidências para sugerir a inclusão da Uncaria tomentosa (Wild.) como possível terapêutica complementar no tratamento da DA. Sua utilização deve ser melhor explorada para aplicação como tratamento complementar as terapêuticas convencionais para a DA

Objective: to explore the mechanisms involved in the triggering and progression of Alzheimer's disease (AD) in order to support the suggestion of the Uncaria Tomentosa (Wild.) plant as another adjuvant therapeutic possibility for the prevention and treatment of AD. Method: This is a narrative review of the literature conducted with a search for articles published on indexed bases and directly in the journals of interest, using as descriptors "Uncária Tomentosa", "Alzheimer's disease", and the respective terms in English. Results: with advances to understand the molecular mechanisms that trigger the effects presented in the development of AD, the various mechanisms of phytocompounds present in the plant suggest its use as neuroprotector, by anti-inflammatory, immunomodulatory and antioxidant mechanisms, whose evidence in the literature is presented to defend its use in this pathology. Conclusion: evidence was found to suggest the inclusion of Uncaria tomentosa (Wild.) as a possible complementary therapy in the treatment of AD. Its use should be better explored for application as a complementary treatment to conventional therapies for AD.

Objetivo: explorar los mecanismos implicados en el desencadenamiento y progresión de la enfermedad de Alzheimer (EA) con el fin de apoyar la sugerencia de la planta Uncaria Tomentosa (silvestre) como otra posibilidad terapéutica adyuvante para la prevención y tratamiento de la EA. Método: Se trata de una revisión narrativa de la literatura realizada con una búsqueda de artículos publicados en bases indexadas y directamente en las revistas de interés, utilizando como descriptores "Uncária Tomentosa", "Alzheimer's disease", y los términos respectivos en inglés. Resultados: con los avances para comprender los mecanismos moleculares que desencadenan los efectos presentados en el desarrollo de la EA, los diversos mecanismos de fitocompuestos presentes en la planta sugieren su uso como neuroprotector, por mecanismos antiinflamatorios, inmunomoduladores y antioxidantes, cuya evidencia en la literatura se presenta para defender su uso en esta patología. Conclusión: se encontró evidencia que sugiere la inclusión de Uncaria tomentosa (Silvestre) como una posible terapia complementaria en el tratamiento de la EA. Su uso debe explorarse mejor para su aplicación como tratamiento complementario a las terapias convencionales para la EA.

Application of the Extracts of Uncaria tomentosa in Endodontics and Oral Medicine: Scoping Review.

BACKGROUND: The main purpose of endodontic treatment is to eliminate the bacteria that are responsible for the contamination and infection of the internal surfaces in order to resolve any pulp or periapical pathology. In fact, some bacteria, such as Enterococcus faecalis, can escape the action of root canal irrigants by aggregating into a biofilm and penetrating deeply into the dentinal tubules. Uncaria tomentosa is a plant belonging to the Rubiaceae family and also commonly known as cat's claw due to the shape and position of the spines; it is a traditional Peruvian medicinal plant of Amazonian origin. Applications in the dental field have been described both in the prevention and treatment of stomatitis and as an antibacterial and anti-inflammatory agent; it has also been investigated as an additive in irrigants and specifically as gels in endodontic cements. The aim of this scoping review is to summarize all the scientific evidence on the possible applications of Uncaria tomentosa extracts in endodontics and, more generally, in oral medicine, in order to understand whether the active ingredients extracted from Uncaria tomentosa can bring a real advantage in endodontics, in the reduction of endodontic failures and in the onset of recurrent endodontic lesions. METHODS: The scoping review was carried out strictly following the PRISMA-ScR checklist; the search was carried out on five databases (PubMed, Scopus, Science Direct, EBSCO and Web of Science) and a register (Cochrane library). RESULTS: The research produced a number of bibliographic sources totaling 2104. With the removal of duplicates, 670 were obtained; potentially eligible articles amounted to 23, of which only seven in vitro studies (four microbiological studies), five clinical studies (three randomized trials) and a case report were included. CONCLUSIONS: From the data in the literature, it can be stated that the active ingredients present in Uncaria tomentosa could represent an interesting product to be used in the endodontic field, both in endocanalary cements and as a gel.

Hybrid Nanoparticles of Proanthocyanidins from Uncaria tomentosa Leaves: QTOF-ESI MS Characterization, Antioxidant Activity and Immune Cellular Response.

Previous studies in Uncaria tomentosa have shown promising results concerning the characterization of polyphenols with leaves yielding more diverse proanthocyanidins and higher bioactivities values. However, the polyphenols-microbiota interaction at the colonic level and their catabolites avoid the beneficial effects that can be exerted by this medicinal plant when consumed. In this regard, a new generation of hybrid nanoparticles has demonstrated improvements in natural compounds' activity by increasing their bioavailability. In this line, we report a detailed study of the characterization of a proanthocyanidin-enriched extract (PA-E) from U. tomentosa leaves from Costa Rica using UPLC-QTOF-ESI MS. Moreover, two types of hybrid nanoparticles, a polymeric-lipid (F-1) and a protein-lipid (F-2) loaded with PA-E were synthesized and their characterization was conducted by dynamic light scattering (DLS), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FT-IR), high-resolution transmission electron microscopy (HR-TEM), and encapsulation efficiency (%EE). In addition, in vitro release, antioxidant activity through 2,2-diphenyl-1-picrylhidrazyl (DPPH) as well as in vivo delayed-type hypersensitivity (DTH) reaction was evaluated. Results allowed the identification of 50 different compounds. The PA-E loaded nanoparticles F-1 and F-2 achieved encapsulation efficiency of ≥92%. The formulations exhibited porosity and spherical shapes with a size average of 26.1 ± 0.8 and 11.8 ± 3.3 nm for F-1 and F-2, respectively. PA-E increased its release rate from the nanoparticles compared to the free extract in water and antioxidant activity in an aqueous solution. In vivo, the delayed-type hypersensitive test shows the higher immune stimulation of the flavan-3-ols with higher molecular weight from U. tomentosa when administered as a nanoformulation, resulting in augmented antigen-specific responses. The present work constitutes to our knowledge, the first report on these bioactivities for proanthocyanidins from Uncaria tomentosa leaves when administrated by nanosystems, hence, enhancing the cellular response in mice, confirming their role in immune modulation.

Uncaria tomentosa (cat's claw): a promising herbal medicine against SARS-CoV-2/ACE-2 junction and SARS-CoV-2 spike protein based on molecular modeling.

COVID-19 is a novel severe acute respiratory syndrome coronavirus. Currently, there is no effective treatment and vaccines seem to be the solution in the future. Virtual screening of potential drugs against the S protein of severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) has provided small molecular compounds with a high binding affinity. Unfortunately, most of these drugs do not attach with the binding interface of the receptor-binding domain (RBD)-angiotensin-converting enzyme-2 (ACE-2) complex in host cells. Molecular modeling was carried out to evaluate the potential antiviral properties of the components of the medicinal herb Uncaria tomentosa (cat's claw) focusing on the binding interface of the RBD-ACE-2 and the viral spike protein. The in silico approach starts with protein-ligand docking of 26 Cat's claw key components followed by molecular dynamics simulations and re-docked calculations. Finally, we carried out drug-likeness calculations for the most qualified cat's claw components. The structural bioinformatics approaches led to the identification of several bioactive compounds of U. tomentosa with potential therapeutic effect by dual strong interaction with interface of the RBD-ACE-2 and the ACE-2 binding site on SARS-CoV-2 RBD viral spike. In addition, in silico drug-likeness indices for these components were calculated and showed good predicted therapeutic profiles of these phytochemicals found in U. tomentosa (cat's claw). Our findings suggest the potential effectiveness of cat's claw as complementary and/or alternative medicine for COVID-19 treatment.Communicated by Ramaswamy H. Sarma.

Study on the Effectiveness of Two Biopolymer Coagulants on Turbidity and Chemical Oxygen Demand Removal in Urban Wastewater.

The present study investigated the effectiveness of two biopolymer coagulants on turbidity and chemical oxygen demand removal in urban wastewater. The biopolymers were produced from vegetal biomass using the mucilage extracted from Opuntia robusta cladodes, and Uncaria tomentosa leaves. Opuntia robusta is an abundant species in Mexico, which is not edible. Uncaria tomentosa is an exotic invasive species in Mexico and other countries, which negatively affects the ecosystems where it is introduced. A combined experimental design of mixture-process was selected to evaluate the effectiveness of both biopolymer coagulants regarding aluminum sulfate (conventional chemical coagulant). Results showed turbidity and chemical oxygen demand removal efficiencies of 42.3% and 69.6% for Opuntia robusta and 17.2% and 39.4% for Uncaria tomentosa biopolymer coagulant, respectively, at a dose of 200 mg/L. Furthermore, optimum conditions from the experimental design to reach the maximum turbidity and chemical oxygen demand removal were obtained at an Opuntia robusta biopolymer coagulant concentration of 10 mg/L, showing removal efficiencies of 68.7 ± 1.7% and 86.1 ± 1.4%, respectively. These results support using Opuntia robusta as an alternative biopolymer coagulant in urban wastewater treatment.

Comparison of the chemical constituents and anti-Alzheimer's disease effects of Uncaria rhynchophylla and Uncaria tomentosa.

BACKGROUND: Uncaria tomentosa, which has similar chemical constituents with Uncaria rhynchophylla, has been reported to alleviate cognitive impairments in Alzheimer's disease (AD) animal models. This study aimed to compare the chemical constituents and anti-AD effect of the ethanol extracts of U. tomentosa (UTE) and U. rhynchophylla (URE). METHODS: The high-performance liquid chromatography (HPLC) was used to compare the chemical constituents of UTE and URE. Streptozotocin (STZ) was intracerebroventricularly (ICV) injected into adult male Sprague-Dawley (SD) rats to establish AD model. UTE (400 mg/kg) or URE (400 mg/kg) was administrated intragastrically once daily to the rats for 6 consecutive weeks. Morris water maze (MWM) test was conducted to assess the neurological functions in the STZ-induced AD rats. The brain tissues of the rats were harvested for further biochemical assay. RESULTS: The MWM test results showed both UTE and URE could significantly improve the learning and memory impairments induced by STZ in rats. Both UTE and URE could significantly inhibit the hyperphosphorylation of tau protein, reduce the elevated levels of pro-inflammatory cytokines (IL-1ß, IL-6 and TNF-α), enhance activities of antioxidant enzymes (SOD, CAT and GPx) and increase the protein expression of HO-1. In addition, UTE could decrease the malondialdehyde (MDA) level. Furthermore, both UTE and URE significantly enhanced Akt activation, down regulated the activation of glycogen synthase kinase 3ß (GSK-3ß), and induced the nuclear translocation of Nrf2 in the STZ-induced AD rats. CONCLUSIONS: UTE and URE contained similar chemical constituents. We found for the first time that both of them could ameliorate cognitive deficits in the STZ-induced AD rats. The underlying molecular mechanism involve suppression of tau hyperphosphorylation, anti-oxidant and anti-neuroinflammation via modulating Akt (Ser473)/GSK3ß (Ser9)-mediated Nrf2 activation. These findings amply implicate that both of UTE and URE are worthy of being developed clinically into pharmaceutical treatment for AD.

Assessment of modulatory activity of Uncaria tomentosa extract against fipronil immunotoxicity in male rats.

This study has investigated the effect of using the Uncaria tomentosa (UT) extract against immunotoxicity that induced by fipronil (FP) in male Wistar rats. Twenty-eight, male Wistar rats were assigned randomly into four groups (7 rats each). Control group received distilled water. FP group received FP 9.7 mg/kg b. wt orally via gastric tube. UT group received 120 mg/kg b. wt. of UT extract orally. FP-UT group received both FP and UT (9.7 and 120 mg/kg b.wt, respectively) for 30 days. Hematological parameters, malondialdehyde (MDA), total antioxidant capacity (TAC), estradiol, histamine and immunoglobulin E (IGE) were assayed. Histopathological and electron microscopical examinations were performed to the lymphoid organs. Hematological parameters, were decreased in the FP group than the control group. There was a rise in MDA of FP group followed by a decrease in TAC content with histological and ultrastructure degenerative changes. UT extract treatment ameliorated the FP-induced perturbations for the former parameters. The results showed that FP treatment exerted an immunotoxic effect through acting as an endocrine disruptor and allergic, pro-inflammatory that was confirmed by histopathological and ultrastructure study of the lymphoid organs. Uncaria tomentosa extract could successfully modulate FP-induced immunotoxicity by diminishing all the studied parameters.

Changes in Human Erythrocyte Membrane Exposed to Aqueous and Ethanolic Extracts from Uncaria tomentosa.

Uncaria tomentosa (Willd.) DC is a woody climber species originating from South and Central America that has been used in the therapy of asthma, rheumatism, hypertension, and blood purification. Our previous study showed that U. tomentosa extracts altered human erythrocyte shape, which could be due to incorporation of the compounds contained in extracts into the erythrocyte membrane. The aim of the present study was to determine how the compounds contained in U. tomentosa extracts incorporate into the human erythrocyte membrane. The study has assessed the effect of aqueous and ethanolic extracts from leaves and bark of U. tomentosa on the osmotic resistance of the human erythrocyte, the viscosity of erythrocyte interior, and the fluidity of erythrocyte plasma membrane. Human erythrocytes were incubated with the studied extracts in the concentrations of 100, 250, and 500 µg/mL for 2, 5, and 24 h. All extracts tested caused a decrease in erythrocyte membrane fluidity and increased erythrocyte osmotic sensitivity. The ethanolic extracts from the bark and leaves increased viscosity of the erythrocytes. The largest changes in the studied parameters were observed in the cells incubated with bark ethanolic extract. We consider that the compounds from U. tomentosa extracts mainly build into the outer, hydrophilic monolayer of the erythrocyte membrane, thus protecting the erythrocytes against the adverse effects of oxidative stress.

Treatment with Uncaria tomentosa Promotes Apoptosis in B16-BL6 Mouse Melanoma Cells and Inhibits the Growth of B16-BL6 Tumours.

Uncaria tomentosa is a medicinal plant native to Peru that has been traditionally used in the treatment of various inflammatory disorders. In this study, the effectiveness of U. tomentosa as an anti-cancer agent was assessed using the growth and survival of B16-BL6 mouse melanoma cells. B16-BL6 cell cultures treated with both ethanol and phosphate-buffered saline (PBS) extracts of U. tomentosa displayed up to 80% lower levels of growth and increased apoptosis compared to vehicle controls. Treatment with ethanolic extracts of Uncaria tomentosa were much more effective than treatment with aqueous extracts. U. tomentosa was also shown to inhibit B16-BL6 cell growth in C57/bl mice in vivo. Mice injected with both the ethanolic and aqueous extracts of U. tomentosa showed a 59 ± 13% decrease in B16-BL6 tumour weight and a 40 ± 9% decrease in tumour size. Histochemical analysis of the B16-BL6 tumours showed a strong reduction in the Ki-67 cell proliferation marker in U. tomentosa-treated mice and a small, but insignificant increase in terminal transferase dUTP nick labelling (TUNEL) staining. Furthermore, U. tomentosa extracts reduced angiogenic markers and reduced the infiltration of T cells into the tumours. Collectively, the results in this study concluded that U. tomentosa has potent anti-cancer activity that significantly inhibited cancer cells in vitro and in vivo.

Extracts from Uncaria tomentosa as antiplatelet agents and thrombin inhibitors - The in vitro and in silico study.

ETHNOPHARMACOLOGICAL RELEVANCE: A wide range of traditional medicine applications of Uncaria tomentosa (Willd. ex Schult.) DC., commonly known as 'vilcacora' or 'cat's claw', includes blood purification, its anticoagulant properties and its use in haemorrhage therapy. AIM OF THE STUDY: Our work is devoted to the effects of ethanol and aqueous extracts (1-50 µg/ml) from U. tomentosa leaves and bark on the haemostatic system. The study is based on two main questions: Can these extracts influence the coagulation cascade of blood plasma or the activation of blood platelets? Do they feature any anticoagulant properties? MATERIALS AND METHODS: Blood platelet aggregation was measured in human platelet-rich plasma; the anticoagulant tests were based on the thrombin, prothrombin and the activated partial thromboplastin time. For the thrombin (TH)-inhibitory activity evaluation, the chromogenic substrate S-2238 and fibrinogen, i.e. physiological substrate for this enzyme, were used. In silico studies included the interactions of TH and the main components of the extracts. RESULTS: The examined extracts demonstrated slight antiplatelet activity. The thrombin time was slightly prolonged. The most efficient TH inhibitor was the ethanolic fraction from leaves (IC50 = 5.86 and 12.48 µg/ml, for the amidolytic and proteolytic assay, respectively). The plant ingredients interacted with TH within and outside the active site, dependently on the compound. The higher binding affinity was found for procyanidins B2 and C1. CONCLUSIONS: The examined extracts demonstrated slight antiplatelet effects; however, they may be promising candidates for the natural inhibitors of TH, which is critical for the formation of fibrin clot.

Uncaria tomentosa improves cognition, memory and learning in middle-aged rats.

Aging accelerates neurodegeneration, while natural and safe neuroprotective agents, such as Uncaria tomentosa, may help to overcome this problem. This study assessed the effects of U. tomentosa extract treatment on the aging process in the brain of Wistar rats. The spatial memory and learning, acetylcholinesterase (AChE) activity, and DNA damage were assessed. Animals of 14 months were tested with different doses of U. tomentosa (5 mg/kg, 15 mg/kg, and 30 mg/kg) and with different durations of treatment (one month and one year). In the Morris Water Maze (MWM), the escape latency was significantly (p < 0.0001) shorter in rats that received 5 mg/kg, 15 mg/kg, and 30 mg/kg of U. tomentosa for both one month and one year of treatment. There was a significant difference in time spent at the platform zone (p < 0.05) of the middle-aged rats treated with U. tomentosa extract for one year when compared to the control rats. The cortex and hippocampus of rats treated with U. tomentosa for one year showed significant (p > 0.05) reduction in AChE activity. DNA damage index on cortex was significantly lower (p < 0.05) in animals treated with 30 mg/kg of U. tomentosa for one month while all the tested doses demonstrated significant (p < 0.001) reductions in DNA damage index in animals treated for one year. In conclusion, U. tomentosa may represent a source of phytochemicals that could enhance memory activity, repair DNA damage, and alter AChE activity, thereby providing neuroprotection during the aging process.

Chinese Herbal Products for Non-Motor Symptoms of Parkinson's Disease in Taiwan: A Population-Based Study.

Objective: Combinations of Chinese herbal products (CHPs) are widely used for Parkinson's disease (PD) in Taiwan. Thereby, we investigated the use of CHPs in patients with PD. Methods: This study was a population-based cohort study that analyzed the data of patients with PD from the National Health Insurance Research Database. A total of 9,117 patients were selected from a random sample of one million individuals included in this database. We used multiple logistic regression models to estimate the adjusted odds ratios of the demographic factors and analyzed the formula and single CHPs commonly used for PD. Results: Traditional Chinese medicine users were more commonly female, younger, of white-collar status, and residents of Central Taiwan. Chaihu-Jia-Longgu-Muli-Tang was the most commonly used formula, followed by Ma-Zi-Ren-Wan and then Shao-Yao-Gan-Cao-Tang. The most commonly used single herb was Uncaria tomentosa (Willd. ex Schult.) DC., followed by Gastrodia elata Blume and then Radix et Rhizoma Rhei (Rheum palmatum L., Rheum tanguticum Maxim. ex Balf., and Rheum officinale Baill.). Chaihu-Jia-Longgu-Muli-Tang and U. tomentosa (Willd. ex Schult.) DC. have shown neuroprotective effects in previous studies, and they have been used for managing non-motor symptoms of PD. Conclusion: Chaihu-Jia-Longgu-Muli-Tang and U. tomentosa (Willd. ex Schult.) DC. are the most commonly used CHPs for PD in Taiwan. Our results revealed the preferences in medication prescriptions for PD. Further studies are warranted to determine the effectiveness of these CHPs for ameliorating the various symptoms of PD, their adverse effects, and the mechanisms underlying their associated neuroprotective effects.

Isolation of mitraphylline from Uncaria tomentosa (Willd. ex Schult.) DC. barks and development of spectrophotometric method for total alkaloids determination in Cat's Claw samples.

INTRODUCTION: The usual quality control for Uncaria tomentosa (Willd. ex Schult.) DC. barks requires highly specific analytical standards and methods based on high-performance liquid chromatography (HPLC), which impacts the costs of the analytical process and the final products. OBJECTIVE: To obtain an analytical reference standard of mitraphylline by isolation from U. tomentosa barks and develop a spectrophotometric method for determination of total alkaloids in samples of U. tomentosa. METHODOLOGY: An alkaloid-enriched extract was obtained by acid-base partition and mitraphylline was selectively precipitated using an 80:20 v/v toluene/hexane solution. The compound was characterised by HPLC-UV/DAD (diode-array detector), mass spectrometry, UV-visible, infrared (IR) and 1 H- and 13 C-nuclear magnetic resonance (NMR) spectroscopy. Sample preparation for the spectrophotometric method consisted of an extraction with boiling methanol (3 × 10 mL, 15 min), followed by a strong cation exchange solid phase extraction (SCX-SPE) clean-up. RESULTS: Mitraphylline with a purity of 98% was isolated in 0.05% m/m yield. All characterisation results were in agreement with previous published data. The spectrophotometric method showed linear range between 0.40 and 20 µg/mL; limits of detection and quantification of 0.15 and 0.49 µg/mg, respectively; dispersion of results lower than 5% for repeatability and intermediate precision; statistically proven accuracy by comparison with reference values obtained by Soxhlet and an HPLC-UV/DAD method; and robustness in relation to sample mass extracted and extraction time. CONCLUSION: The methods developed to obtain mitraphylline analytical standard from U. tomentosa barks and to determine total alkaloids by spectrophotometry provided a cheaper and faster quality control alternative for U. tomentosa samples.

Antioxidant Activity of an Aqueous Leaf Extract from Uncaria tomentosa and Its Major Alkaloids Mitraphylline and Isomitraphylline in Caenorhabditis elegans.

Uncaria tomentosa (Rubiaceae) has a recognized therapeutic potential against various diseases associated with oxidative stress. The aim of this research was to evaluate the antioxidant potential of an aqueous leaf extract (ALE) from U. tomentosa, and its major alkaloids mitraphylline and isomitraphylline. The antioxidant activity of ALE was investigated in vitro using standard assays (DPPH, ABTS and FRAP), while the in vivo activity and mode of action were studied using Caenorhabditis elegans as a model organism. The purified alkaloids did not exhibit antioxidant effects in vivo. ALE reduced the accumulation of reactive oxygen species (ROS) in wild-type worms, and was able to rescue the worms from a lethal dose of the pro-oxidant juglone. The ALE treatment led to a decreased expression of the oxidative stress response related genes sod-3, gst-4, and hsp-16.2. The treatment of mutant worms lacking the DAF-16 transcription factor with ALE resulted in a significant reduction of ROS levels. Contrarily, the extract had a pro-oxidant effect in the worms lacking the SKN-1 transcription factor. Our results suggest that the antioxidant activity of ALE in C. elegans is independent of its alkaloid content, and that SKN-1 is required for ALE-mediated stress resistance.

Glucoindole alkaloid accumulation induced by yeast extract in Uncaria tomentosa root cultures is involved in defense response.

OBJECTIVE: To evaluate the induction of monoterpenoid indole alkaloids (MIA) and phenolic compound production by yeast extract (YE) and its relationship with defense responses in Uncaria tomentosa (Rubiaceae) root cultures. RESULTS: Root cultures were elicited by YE at three concentrations. The 0.5 mg YE ml-1 treatment did not affect cell viability but increased the hydrogen peroxide concentration by 5.7 times; guaiacol peroxidase activity by twofold; and the glucoindole alkaloid 3α-dihydrocadambine (DHC) content by 2.6 times (to 825.3 ± 27.3 µg g-1). This treatment did not affect the contents of monoterpenoid oxindole alkaloids or chlorogenic acids. In response to 0.5 mg YE ml-1 treatment, the transcript levels of MIA biosynthetic genes, TDC and LAMT, increased 5.4 and 1.9-fold, respectively, that of SGD decreased by 32%, and that of STR did not change. The transcript levels of genes related to phenolic compounds, PAL, CHS and HQT, increased by 1.7, 7.7, and 1.2-fold, respectively. Notably, the transcript levels of Prx1 and Prx encoding class III peroxidases increased by 1.4 and 2.5-fold. CONCLUSION: The YE elicitor induced an antioxidant defense response, increased the transcript levels of genes encoding enzymes related to strictosidine biosynthesis precursors and class III peroxidases, and decreased the transcript level of SGD. Thus, YE could stimulate antifungal DHC production in root cultures of U. tomentosa.