Moscatilin, a potential therapeutic agent for cancer treatment: insights into molecular mechanisms and clinical prospects.

Moscatilin, a bibenzyl derivative from the Dendrobium genus, has been traditionally used in Chinese medicine. Recent studies suggest its potential as a powerful anticancer agent due to its diverse pharmacological properties.This review aims to consolidate current research on moscatilin's anticancer mechanisms, structure-activity relationships, and therapeutic potential to assess its viability for clinical use. A literature search was performed in PubMed/MedLine, Scopus, and Web of Science.The search focused on "cancer," "moscatilin," "anticancer," "bioactivity," "dendrobium," and "pharmacological properties." Relevant studies on molecular mechanisms, preclinical and clinical efficacy, and bioavailability were reviewed. Moscatilin exhibits significant anticancer effects in lung, breast, colorectal, and pancreatic cancers. It induces apoptosis via the JNK/SAPK pathway, inhibits cell proliferation, and suppresses metastasis. Structure-activity relationship studies reveal that phenolic groups and a two-carbon bridge are crucial for its efficacy. Additionally, moscatilin shows good bioavailability and a favorable safety profile, with low toxicity to healthy cells. Moscatilin demonstrates considerable potential as an anticancer agent, targeting multiple cancer progression pathways. Further clinical trials are essential to confirm its therapeutic efficacy and safety in humans.

Comprehensive elucidation of the differential physiological kale response to cytokinins under in vitro conditions.

BACKGROUND: Kale, a versatile cruciferous crop, valued for its pro-health benefits, stress resistance, and potential applications in forage and cosmetics, holds promise for further enhancement of its bioactive compounds through in vitro cultivation methods. Micropropagation techniques use cytokinins (CKs) which are characterized by various proliferative efficiency. Despite the extensive knowledge regarding CKs, there remains a gap in understanding their role in the physiological mechanisms. That is why, here we investigated the effects of three CKs - kinetin (Kin), 6-benzylaminopurine (BAP), and 2-isopentenyladenine (2iP) - on kale physiology, antioxidant status, steroidal metabolism, and membrane integrity under in vitro cultivation. RESULTS: Our study revealed that while BAP and 2iP stimulated shoot proliferation, they concurrently diminished pigment levels and photosynthetic efficiency. Heightened metabolic activity in response to all CKs was reflected by increased respiratory rate. Despite the differential burst of ROS, the antioxidant properties of kale were associated with the upregulation of guaiacol peroxidase and the scavenging properties of ascorbate rather than glutathione. Notably, CKs fostered the synthesis of sterols, particularly sitosterol, pivotal for cell proliferation and structure of membranes which are strongly disrupted under the action of BAP and 2iP possibly via pathway related to phospholipase D and lipoxygenase which were upregulated. Intriguingly, both CKs treatment spurred the accumulation of sitostenone, known for its ROS scavenging and therapeutic potential. The differential effects of CKs on brassicasterol levels and brassinosteroid (BRs) receptor suggest potential interactions between CKs and BRs. CONCLUSION: Based on the presented results we conclude that the effect evoked by BAP and 2iP in vitro can improve the industrial significance of kale because this treatment makes possible to control proliferation and/or biosynthesis routes of valuable beneficial compounds. Our work offers significant insights into the nuanced effects of CKs on kale physiology and metabolism, illuminating potential avenues for their application in plant biotechnology and medicinal research.

(5S)-5-Benzylswainsonines as potent and selective inhibitors of Golgi α-mannosidase II: synthesis, enzyme evaluation and molecular modelling.

Development of novel anti-cancer therapeutics based on Golgi α-mannosidase II (GMII) inhibition is considerably impeded by an undesired co-inhibition of lysosomal α-mannosidase leading to severe side-effects. In this contribution, we describe a fully stereoselective synthesis of (5S)-5-[4-(halo)benzyl]swainsonines as highly potent and selective inhibitors of GMII. The synthesis starts from a previously reported aldehyde readily available from l-ribose, and the key features include an intramolecular reductive amination with substrate-controlled stereoselectivity and a late-stage derivatisation of the benzyl group via ipso-substitution. These novel swainsonine analogues were found to be nanomolar inhibitors of the Golgi-type α-mannosidase AMAN-2 (Ki = 23-75 nM) with excellent selectivity (selectivity index = 205-870) over the lysosomal-type Jack bean α-mannosidase. Finally, molecular docking and pKa calculations were performed to provide more insight into the structure of the inhibitor:enzyme complexes, and a pair interaction energy analysis (FMO-PIEDA) was carried out to rationalise the observed potency and selectivity of the inhibitors.

Elicitors directed in vitro growth and production of stevioside and other secondary metabolites in Stevia rebaudiana (Bertoni) Bertoni.

Stevia rebaudiana (stevia) is a plant in the Asteraceae that contains several biologically active compounds including the antidiabetic diterpene glycosides (e.g. stevioside, rebaudioside and dulcoside) that can serve as zero-calorie sugar alternatives. In this study, an elicitation strategy was applied using 5% polyethylene glycol (PEG), sodium chloride (NaCl; 50 and 100 mM) and gibberellic acid (2.0 and 4.0 mg/L GA3) to investigate their effect on shoot morphogenesis, and the production of phenolics, flavonoids, total soluble sugars, proline and stevioside, as well as antioxidant activity, in shoot cultures of S. rebaudiana. Herewith, the media supplemented with 2 mg/L and 4 mg/L GA3 exhibited the highest shooting response (87% and 80%). The augmentation of lower concentrations of GA3 (2 mg/L) in combination with 6-benzylaminopurine (BAP) resulted in the maximum mean shoot length (11.1 cm). The addition of 100 mM NaCl salts to the media led to the highest observed total phenolics content (TPC; 4.11 mg/g-DW compared to the control 0.52 mg/g-DW), total flavonoids content (TFC; 1.26 mg/g-DW) and polyphenolics concentration (5.39 mg/g-DW) in shoots cultured. However, the maximum antioxidant activity (81.8%) was observed in shoots raised in media treated with 50 mM NaCl. The application of 2 mg/L of GA3 resulted in the highest accumulation of proline (0.99 µg/mL) as compared to controls (0.37 µg/mL). Maximum stevioside content (71 µL/mL) was observed in cultures supplemented with 100 mM NaCl and 5% PEG, followed by the 4 mg/L GA3 treatment (70 µL/mL) as compared to control (60 µL/mL). Positive correlation was observed between GA3 and stevioside content. Notably, these two compounds are derived from a shared biochemical pathway. These results suggest that elicitation is an effective option to enhance the accumulation of steviosides and other metabolites and provides the groundwork for future industrial scale production using bioreactors.

In Vivo Ocular Pharmacokinetics and Toxicity of Siponimod in Albino Rabbits.

Siponimod is a promising agent for the inhibition of ocular neovascularization in diabetic retinopathy and age-related macular degeneration. Siponimod's development for ophthalmological application is hindered by the limited information available on the drug's solubility, stability, ocular pharmacokinetics (PK), and toxicity in vivo. In this study, we investigated the aqueous stability of siponimod under stress conditions (up to 60 °C) and its degradation behavior in solution. Additionally, siponimod's ocular PK and toxicity were investigated using intravitreal injection of two different doses (either 1300 or 6500 ng) in an albino rabbit model. Siponimod concentration was quantified in the extracted vitreous, and the PK parameters were calculated. The drug half-life after administration of the low and high doses was 2.8 and 3.9 h, respectively. The data obtained in vivo was used to test the ability of published in silico models to predict siponimod's PK accurately. Two models that correlated siponimod's molecular descriptors with its elimination from the vitreous closely predicted the half-life. Furthermore, 24 h and 7 days after intravitreal injections, the retinas showed no signs of toxicity. This study provides important information necessary for the formulation and development of siponimod for ophthalmologic applications. The short half-life of siponimod necessitates the development of a sustained drug delivery system to maintain therapeutic concentrations over an extended period, while the lack of short-term ocular toxicity observed in the retinas of siponimod-treated rabbits supports possible clinical use.

ONC206 targeting ClpP induces mitochondrial dysfunction and protective autophagy in hepatocellular carcinoma cells.

Hepatocellular carcinoma (HCC) is the most common form of liver cancer, accounting for approximately 90 % of all cases. ONC201, a member of the imipridone drug family, has shown promising therapeutic potential and a good safety profile in both malignant pediatric central nervous system tumors (diffuse midline glioma [DMG]) and hematologic malignancies. ONC206 is a more potent analog of ONC201. However, the ONC206 potential and mechanism of action in HCC remain to be elucidated. We found that ONC206 hindered HCC growth by suppressing cell proliferation and inducing apoptosis. Moreover, ONC206 induced cytoprotective autophagy, and blocking autophagy enhanced the proapoptotic effect of ONC206. Additionally, ONC206 induced mitochondrial swelling, reduced the mitochondrial membrane potential (MMP), and led to the accumulation of mitochondrial ROS in HCC cells, ultimately resulting in mitochondrial dysfunction. The HCC patient samples exhibited notably elevated levels of caseinolytic protease proteolytic subunit (ClpP), which serves as a mediator of ONC206-induced mitochondrial dysfunction and the activation of protective autophagy. knockdown of ClpP reversed the cytotoxic effects of ONC206 on HCC cells. In summary, our results provide the first insight into the mechanism by which ONC206 exerts its anti-HCC effects and induces protective autophagy in HCC cells through ClpP.

Mechanistic evaluation of myristicin on apoptosis and cell cycle regulation in breast cancer cells.

The current study was focused on the anticancer activity of myristicin against MCF-7 human breast cancer (BC) cells. BC is the most common and leading malignant disease in women worldwide. Now-a-days, various conventional therapies are used against BC and still represent a chief challenge because those treatments fail to differentiate normal cells from malignant cells, and they have severe side effects also. So, there is a need develop new therapies to decrease BC-related morbidity and mortality. Myristicin, a 1­allyl­5­methoxy­3, 4­methylenedioxybenzene, is a main active aromatic compound present in various spices, such as nutmeg, mace, carrot, cinnamon, parsely and some essential oils. Myristicin has a wide range of effects, including antitumor, antioxidative and antimicrobial activity. Nevertheless, the effects of myristicin on human BC cells remain largely unrevealed. The cytotoxicity effect of myristicin on MCF­7 cells was increased dose dependently detected by (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Lactate Dehydrogenase assays. Myristicin was found to be significantly inducing the cell apoptosis, as compared to control, using acridine orange/ethidium bromide, Hoechst stain and annexin V. Moreover, it activates cell antimigration, intracellular reactive oxygen species generation and cell cycle arrest in the G1/S phase. In addition, myristicin induces the expression of apoptosis and cell cycle genes (Caspases8, Bax, Bid, Bcl2, PARP, p53, and Cdk1) was demonstrated by quantitative polymerase chain reaction and apoptosis proteins (c-PARP, Caspase 9, Cytochrome C, PDI) expression was also analyzed with western blot. Overall, we illustrated that myristicin could regulate apoptosis signaling pathways in MCF-7 BC cells.

Repurposing the multiple sclerosis drug Siponimod for osteoporosis treatment.

Osteoporosis is the most common bone disorder, in which an imbalance between osteoclastic bone resorption and osteoblastic bone formation disrupts bone homeostasis. Osteoporosis management using anti-osteoclastic agents is a promising strategy; however, this remains an unmet need. Sphingosine-1-phosphate (S1P) and its receptors (S1PRs) are essential for maintaining bone homeostasis. Here, we identified that Siponimod, a Food and Drug Administration-approved S1PR antagonist for the treatment of multiple sclerosis, shows promising therapeutic effects against osteoporosis by inhibiting osteoclast formation and function. We found that Siponimod inhibited osteoclast formation in a dose-dependent manner without causing cytotoxicity. Podosome belt staining and bone resorption assays indicated that Siponimod treatment impaired osteoclast function. Western blot and qPCR assays demonstrated that Siponimod suppressed the expression of osteoclast-specific markers, including C-Fos, Nftac1, and Ctsk. Mechanistically, we validated that Siponimod downregulated receptor activator of nuclear factor kappa B ligand (RANKL)-induced Mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signaling pathways during osteoclastogenesis. Moreover, in a preclinical mouse model, Siponimod prevented ovariectomy-induced bone loss by suppressing osteoclast activity in vivo. Collectively, these results suggest that Siponimod could serve as an alternative therapeutic agent for the treatment of osteoporosis.

ONC212 enhances YM155 cytotoxicity by triggering SLC35F2 expression and NOXA-dependent MCL1 degradation in acute myeloid leukemia cells.

Although the anticancer activity of ONC212 has been reported, the precise mechanism underlying its apoptotic effects remains unclear. In this study, we investigated the apoptotic mechanism of ONC212 in acute myeloid leukemia (AML) cells. ONC212 induces apoptosis, MCL1 downregulation, and mitochondrial depolarization in AML U937 cells. Ectopic MCL1 expression alleviates mitochondria-mediated apoptosis in ONC212-treated U937 cells. ONC212 triggers AKT phosphorylation, inducing NOX4-dependent ROS production and promoting HuR transcription. HuR-mediated ATF4 mRNA stabilization stimulates NOXA and SLC35F2 expression; ONC212-induced upregulation of NOXA leads to MCL1 degradation. The synergistic effect of ONC212 on YM155 cytotoxicity was dependent on increased SLC35F2 expression. In addition, YM155 feedback facilitated the activation of the ONC212-induced signaling pathway. A similar mechanism explains ONC212- and ONC212/YM155-induced AML HL-60 cell death. The continuous treatment of U937 cells with the benzene metabolite hydroquinone (HQ) generated U937/HQ cells, exhibiting enhanced responsiveness to the cytotoxic effects of ONC212. In U937/HQ cells, ONC212 triggered apoptosis through NOXA-mediated MCL1 downregulation, enhancing YM155 cytotoxicity. Collectively, our data suggested that ONC212 upregulated SLC35F2 expression and triggered NOXA-mediated MCL1 degradation in U937, U937/HQ, and HL-60 cells by activating the AKT/NOX4/HuR/ATF4 pathway. The ONC212-induced signaling pathway showed anti-AML activity and enhanced YM155 cytotoxicity.

Siponimod Attenuates Neuronal Cell Death Triggered by Neuroinflammation via NFκB and Mitochondrial Pathways.

Multiple sclerosis (MS) is the most common autoimmune demyelinating disease of the central nervous system (CNS), consisting of heterogeneous clinical courses varying from relapsing-remitting MS (RRMS), in which disability is linked to bouts of inflammation, to progressive disease such as primary progressive MS (PPMS) and secondary progressive MS (SPMS), in which neurological disability is thought to be linked to neurodegeneration. As a result, successful therapeutics for progressive MS likely need to have both anti-inflammatory and direct neuroprotective properties. The modulation of sphingosine-1-phosphate (S1P) receptors has been implicated in neuroprotection in preclinical animal models. Siponimod/BAF312, the first oral treatment approved for SPMS, may have direct neuroprotective benefits mediated by its activity as a selective (S1P receptor 1) S1P1 and (S1P receptor 5) S1P5 modulator. We showed that S1P1 was mainly present in cortical neurons in lesioned areas of the MS brain. To gain a better understanding of the neuroprotective effects of siponimod in MS, we used both rat neurons and human-induced pluripotent stem cell (iPSC)-derived neurons treated with the neuroinflammatory cytokine tumor necrosis factor-alpha (TNF-α). Cell survival/apoptotic assays using flow cytometry and IncuCyte live cell analyses showed that siponimod decreased TNF-α induced neuronal cell apoptosis in both rat and human iPSCs. Importantly, a transcriptomic analysis revealed that mitochondrial oxidative phosphorylation, NFκB and cytokine signaling pathways contributed to siponimod's neuroprotective effects. Our data suggest that the neuroprotection of siponimod/BAF312 likely involves the relief of oxidative stress in neuronal cells. Further studies are needed to explore the molecular mechanisms of such interactions to determine the relationship between mitochondrial dysfunction and neuroinflammation/neurodegeneration.

Potent, selective and reversible hMAO-B inhibition by benzalphthalides: Synthesis, enzymatic and cellular evaluations and virtual docking and predictive studies.

Monoaminooxidases (MAOs) are important targets for drugs used in the treatment of neurological and psychiatric disorders and particularly on Parkinson's Disease (PD). Compounds containing a trans-stilbenoid skeleton have demonstrated good selective and reversible MAO-B inhibition. Here, twenty-two (Z)-3-benzylidenephthalides (benzalphthalides, BPHs) displaying a trans-stilbenoid skeleton have been synthesised and evaluated as inhibitors of the MAO-A and MAO-B isoforms. Some BPHs have selectively inhibited MAO-B, with IC50 values ranging from sub-nM to µM. The most potent compound with IC50 = 0.6 nM was the 3',4'-dichloro-BPH 16, which showed highly selective and reversible MAO-B inhibitory activity. Furthermore, the most selective BPHs displayed a significant protection against the apoptosis, and mitochondrial toxic effects induced by 6-hydroxydopamine (6OHDA) on SH-SY5Y cells, used as a cellular model of PD. The results of virtual binding studies on the most potent compounds docked in MAO-B and MAO-A were in agreement with the potencies and selectivity indexes found experimentally. Additionally, related to toxicity risks, drug-likeness and ADME properties, the predictions found for the most relevant BPHs in this research were within those ranges established for drug candidates.

De novo in vitro shoot morphogenesis from shoot tip-induced callus cultures of Gymnema sylvestre (Retz.) R. Br. ex Sm

BACKGROUND: Gymnema sylvestre is a medicinal woody perennial vine known for its sweetening properties and antidiabetic therapeutic uses in the modern and traditional medicines. Its over-exploitation for the therapeutic uses and to meet the demand of pharmaceutical industry in raw materials supply for the production of anti-diabetic drugs has led to considerable decline in its natural population. RESULTS: An efficient system of shoot bud sprouting from nodal segment explants and indirect plant regeneration from apical meristem-induced callus cultures of G. sylvestre have been developed on Murashige and Skoog (MS) medium amended with concentrations of cytokinins. Of the three growth regulators tested, N6-benzylaminopurine (BAP) was the most efficient and 2.0 mg L-1 gave the best shoot formation efficiency. This was followed by thidiazuron (TDZ) and kinetin (Kin) but, most of the TDZ-induced micro shoots showed stunted growth. Multiple shoot formation was observed on medium amended with BAP or TDZ at higher concentrations. The produced micro shoots were rooted on half strength MS medium amended with auxins and rooted plantlets acclimatized with 87% survival of the regenerates. CONCLUSIONS: The developed regeneration system can be exploited for genetic transformation studies, particularly when aimed at producing its high yielding cell lines for the anti-diabetic phytochemicals. It also offers opportunities for exploring the expression of totipotency in the anti-diabetic perennial vine.

In vitro propagation of Vitis vinifera L. cv. 'Monastrell'

Background: A protocol for the micropropagation of the grape (Vitis vinifera L.) cultivar 'Monastrell' was developed. Initial plant material was obtained from the sanitary selection of grapevine plants performed by real-time RT-PCR to confirm the absence of Grapevine fanleaf virus, Arabis mosaic virus, Grapevine leafroll-associated virus 1, Grapevine leafroll-associated virus 3, and Grapevine fleck virus. Results: The effects of the salt composition (comparing Lloyd and McCown woody plant medium and Murashige and Skoog medium 1/2 macronutrients) and the growth regulator benzylaminopurine (BAP), at 0 and 8.9 µM, on plant propagation were evaluated using nodes as explants. The most efficient procedure consisted of bud induction in the medium with Lloyd and McCown woody plant salts and 8.9 µM BAP for 30 d along with elongation in cytokinin-free medium for 60 d, which gave 22 nodes/explant (174 plants/initial plant). A second cycle of propagation in a medium without BAP for another 60 d could give approximately 10,000 nodes, which can be obtained after an additional 2 months of culture. All plants acclimatized after the second cycle of multiplication were successfully transferred to soil. Conclusion: We developed an optimal protocol for V. vinifera cv. 'Monastrell' micropropagation, the first described for this cultivar.

Meristem culture and subsequent micropropagation of Chilean strawberry (Fragaria chiloensis (L) Duch. )

BACKGROUND: Vegetative propagation of Fragaria sp. is traditionally carried out using stolons. This system of propagation, in addition to being slow, can spread plant diseases, particularly serious being viral. In vitro culture of meristems and the establishment of micropropagation protocols are important tools for solving these problems. In recent years, considerable effort has been made to develop in vitro propagation of the commercial strawberry in order to produce virus-free plants of high quality. These previous results can serve as the basis for developing in vitro-based propagation technologies in the less studied species Fragaria chiloensis. RESULTS: In this context, we studied the cultivation of meristems and establishment of a micropropagation protocol for F. chiloensis. The addition of polyvinylpyrrolidone (PVP) improved the meristem regeneration efficiency of F. chiloensis accessions. Similarly, the use of 6-benzylaminopurine (BAP) in the culture media increased the average rate of multiplication to 3-6 shoots per plant. In addition, the use of 6-benzylaminopurine (BAP), had low levels (near zero) of explant losses due to oxidation. However, plant height as well as number of leaves and roots were higher in media without growth regulators, with average values of 0.5 cm, 9 leaves and 4 roots per plant. CONCLUSIONS: For the first time in Chilean strawberry, meristem culture demonstrated to be an efficient tool for eliminating virus from infected plants, giving the possibility to produce disease free propagation material. Also, the addition of PVP into the basal MS medium improved the efficiency of plant recovery from isolated meristems. Farmers can now access to high quality plant material produced by biotech tools which will improve their technological practices.

Antibacterial activity of the Piper aduncum oil and dillapiole, its main constituent, against multidrug-resistant strains / Actividad antibacteriana del aceite de Piper aduncum y dillapiole, su componente principal, frente a cepas resistentes a múltiples fármacos

The study aimed to evaluate the bactericidal activity of oil essential and dillapiole from P. aduncum against standard and multidrug-resistant strains of Staphylococcus spp. The oil showed antimicrobial action against these strains, but better results were obtained for the standards strains of S. epidermidis and S. aureus, with MIC of 250 and 500 ug/mL, respectively. Dillapiolle was less effective than the oil against the same standard and multi-drug resistant strains (MIC =1000 ug/mL). However, when dillapiolle was tested in combination with myristicin, another component of the oil, it increased its bactericidal activity and showed a synergistic action...

El objetivo del estudio fue evaluar la actividad bactericida de los aceites esenciales y dillapiole de P. aduncum contra cepas estándar y multirresistentes de Staphylococcus spp. El aceite mostró acción antimicrobiana frente a estas cepas, pero se obtuvo mejores resultados para las cepas de S. epidermidis y S. aureus, con MIC de 250 y 500 ug/ml, respectivamente. Dillapiolle fue menos eficaz que el aceite contra cepas estándar y multirresistentes (MIC = 1000 ug/ml). Sin embargo, cuando dillapiolle fue probado en combinación con la miristicina, otro componente del aceite, que aumentó su actividad bactericida y mostró una acción sinérgica...

Whole cells in enantioselective reduction of benzyl acetoacetate

The β-ketoester benzyl acetoacetate was enantioselectively reduced to benzyl (S)-3-hydroxybutanoate by seven microorganism species. The best result using free cells was obtained with the yeast Hansenula sp., which furnished 97% ee and 85% of conversion within 24 h. After immobilization in calcium alginate spheres, K.marxianus showed to be more stable after 2 cycles of reaction.

Rapid in vitro plant regeneration from leaf explants of Launaea sarmentosa (Willd.) Sch. Bip. ex Kuntze

An efficient protocol for organogenesis through leaves has been established for Launaea sarmentosa (Willd.) Sch. Bip. ex Kuntze, a highly valuable medicinal plant. The leaf explants produced microshoots on MS basal medium when fortified with cytokinins and auxins. A combination of 6-benzylaminopurine (BAP) at 0.5mg/l and naphthaleneacetic acid (NAA) at 0.2mg/l resulted in the induction of high frequency microshoots in 30 days. The microshoots were successfully subcultured for shoot elongation and eventually for rooting on MS medium supplemented with indole-3-butyric acid (IBA) at 0.5mg/l. The regenerated plantlets were hardened under greenhouse conditions and transferred to garden, resulting in a 90% survival rate.

Inhibitory effect of jasmonic acid and ethylene on epicotyl growth and bud induction in the maritime pine, Pinus pinaster Soland. in Ait

Two independent parameters, epicotyl height (cm) and number of induced buds were studied on Pinus pinaster explants to analyse the effects of three phytohormones (6-benzylaminopurine, jasmonic acid, ethylene) which were combined or not in 11 different treatments. Epicotyle length diminished significantly in relation to the control medium (medium without exogen phytohormones) in presence of jasmonic acid, 6-benzylaminopurine or Ethephon (which is converted to ethylene in plants) in any of treatments. Concentrations of 100 microM of jasmonic acid and Ethephon had a greater inhibitory effect than the treatments with 10 microM. In addition to that, jasmonic acid was a stronger inhibitor than Ethephon in any of the tried combinations. There were no significant differences between the control treatment and the treatment s with only 10 microM of jasmonic acid or Ethephon. However, 10 microM 6-benzylaminopurine induced bud formation. The different combinations of 6-benzylaminopurine with jasmonic acid and Ethephon showed that concentrations of 10 to 100 microM did not affect the number of induced buds. Jasmonic acid had an inhibitory effect which Ethephon only showed when combined with 100 microM of jasmonic acid and 10 microM of 6-benzylaminopurine. Three response groups were defined by cluster analysis: group 1 produced the greatest mean number of buds (4 to 5) and a mean epicotyl growth of 1 to 1.5 cm; group 2 produced 2 to 4 buds and a mean growth of 0.5 to 1.2 cm; group 3 produced only one bud and a mean epicotyl length of 1.2 to 2 cm.

Implications of dibenzyl trisulphide for disease treatment based on its mode of action / Implicaciones del trisulfuro de dibencilo para el tratamiento de enfermedades a partir de su modo de acción

Studies conducted on the secondary metabolite (natural product), dibenzyl trisulphide (DTS), which was isolated from the sub-tropical shrub Petiveria alliacea (guinea hen weed, anamu) [Phytolaccaceae] have shown tremendous pharmaceutical promise as a drug prototype. This is now reflected in the development of the broad spectrum anti-cancer molecule, fluorapacin (bis(4-fluorobenzyl) trisulphide) which has an excellent safety profile. The mode of action elucidated for DTS is the mitogen activated protein extracellular regulated kinases 1 and 2 (MAPKinases ERK 1 and ERK 2). The MAPKinase signal transduction biochemical pathways are important in the regulation of a wide range of cellular processes which are important in disease establishment. These processes include: cancer cell proliferation, nerve repair, memory enhancement, autoimmune diseases, which are linked to thymic cell involution and bone marrow functions, cerebrovascular and cardiovascular diseases. In addition to the MAPkinase signal transduction mode of action, DTS also prevents the denaturation of serum albumin which is a feature of nonsteroidal anti-inflammatory drugs, thus supporting the molecule's possible role in the treatment of inflammatory ageing diseases.

Los estudios realizados sobre el metabolito secundario (producto natural), trisulfuro de dibencilo (TSD), que fue aislado del arbusto subtropical Petiveria alliacea (hierba de guinea, anamú) [Phytolaccaceae] muestran que se trata de una tremenda promesa farmacéutica como prototipo de droga. Esto se refleja actualmente en el desarrollo de la molécula anticancerígena de amplio espectro, la fluorapacina (bis (4-fluorobencilo) trisulfuro) que posee un excelente perfil de seguridad. El modo de acción para el TSD se explica partiendo de las proteínas quinasas 1 y 2 activadas por mitógenos y reguladas por señales extracelulares (Quinasas MAP ERK 1 y ERK 2). Las vías bioquímicas de transducción de la señal de la quinasa MAP, son importantes en la regulación de una amplia variedad de procesos celulares, importantes a la hora de determinar una enfermedad. Dichos procesos comprenden: la proliferación de la célula cancerosa, la reparación de nervios, el mejoramiento de la memoria, y las enfermedades autoinmunes, vinculadas con la involución tímica y las funciones de la médula, las enfermedades cerebrovasculares y cardiovasculares. Además del modo de acción de las transducción de señales de la quinasa MAP, el TSD previene también la desnaturalización de la albúmina sérica, lo cual constituye una característica de las drogas anti-inflamatorias no esferoidales, apoyando así el posible papel de las moléculas en el tratamiento de las enfermedades inflamatorias en el proceso de envejecimiento.