Pharmacological properties of Hoya (Apocynaceae): a systematic review

In tropical forests, Hoya, a plant with significant indigenous medicinal applications, has been underexplored in pharmacological studies. This systematic review meticulously investigates the diverse pharmacological effects exhibited by various Hoya species on human health. A comprehensive literature search, encompassing Scopus, ScienceDirect, and SpringerLink databases, employed specific keyword combinations ('Hoya' and 'pharmacological properties' OR 'pharmacology property'). The included studies exclusively focused on Hoya's impact on human health. The findings underscore Hoya's potential as a medicinal plant, demonstrating promising attributes such as anticancer, antibacterial, antioxidant, anti-inflammatory, anti-diabetic, antinociceptive, and parasympatholytic effects. Despite these promising indications, the review underscores the necessity for further in vivo investigations to fully unlock Hoya's therapeutic potential. A comprehensive understanding of its mechanisms of action, efficacy, and safety in living systems is imperative for realising its holistic therapeutic benefits.

Unraveling the Molecular Reason of Opposing Effects of α-Mangostin and Norfluoxetine on TREK-2 at the Same Binding Site

TWIK-related K+ channel (TREK)-2, expressed in sensory neurons, is involved in setting membrane potential, and its modulations contributes to the generation of nociceptive signals. Although acute and chronic pain is a common symptom experienced by patients with various conditions, most existing analgesics exhibit low efficacy and are associated with adverse effects. For this reason, finding the novel modulator of TREK-2 is of significance for the development of new analgesics. Recent studies have shown that α-Mangostin (α-MG) activates TREK-2, facilitating analgesic effects, yet the underlying molecular mechanisms remain elusive. Intriguingly, even though norfluoxetine (NFx) is known to inhibit TREK-2, α-MG is also observed to share a same binding site with NFx, and this implies that TREK-2 might be modulated in a highly complicated manner. Therefore, we examine the mechanism of how TREK-2 is activated by α-MG using computational methods and patch clamp experiments in the present study. Based on these results, we offer an explanation of how α-MG and NFx exhibit opposing effects at the same binding site of TREK-2. These findings will broaden our understanding of TREK-2 modulation, providing clues for designing novel analgesic drugs.

Updating the Pharmacological Effects of α-Mangostin Compound and Unraveling Its Mechanism of Action: A Computational Study Review

α-Mangostin, initially identified in 1855, is a xanthone derivative compound predominantly located in the pericarp of the mangosteen fruit (Garcinia mangostana L). This compound is known for its beneficial properties as an antioxidant and anti-inflammatory agent, still holding promise for potential benefits in other related pathologies. In the investigative process, computational studies have proven highly valuable in providing evidence and initial screening before progressing to preclinical and clinical studies. This review aims to present the pharmacological findings and mechanisms of action of α-mangostin based on computational studies. The compilation of this review is founded on the analysis of relevant articles obtained from PubMed, Scopus, and ScienceDirect databases. The study commences with an elucidation of the physicochemical characteristics, drug-likeness, pharmacokinetics, and toxicity profile of α-mangostin, which demonstrates that α-mangostin complies with the Lipinski's Rule of Five, exhibits favorable profiles of absorption, distribution, metabolism, and excretion, and presents low toxicity. Subsequent investigations have revealed that computational studies employing various software tools including ArgusLab, AutoDock, AutoDock Vina, Glide, HEX, and MOE, have been pivotal to comprehend the pharmacology of α-mangostin. Beyond its well established roles as an antioxidant and anti-inflammatory agent, α-mangostin is now recognized for its pharmacological effects in Alzheimer's disease, diabetes, cancer, chronic kidney disease, chronic periodontitis, infectious diseases, and rheumatoid arthritis. Moreover, α-mangostin is projected to have applications in pain management and as a potent mosquito larvicide. All of these findings are based on the attainment of adequate binding affinity to specific target receptors associated with each respective pathological condition. Consequently, it is anticipated that these findings will serve as a foundation for future scientific endeavours, encompassing both in vitro and in vivo studies, as well as clinical investigations, to better understand the pharmacological effects of α-mangostin.

Multi-target modulation of ion channels underlying the analgesic effects of α-mangostin in dorsal root ganglion neurons

BACKGROUND

α-Mangostin is a xanthone isolated from the pericarps of mangosteen fruit with, and has analgesic properties. Although the effects suggest an interaction of α-mangostin with ion channels in the nociceptive neurons, electrophysiological investigation of the underlying mechanism has not been performed.

HYPOTHESIS

We hypothesized that α-Mangostin exerts its analgesic effects by modulating the activity of various ion channels in dorsal root ganglion (DRG) neurons.

METHODS

We performed a whole-cell patch clamp study using mouse DRG neurons, HEK293T cells overexpressing targeted ion channels, and ND7/23 cells. Molecular docking (MD) and in silico absorption, distribution, metabolism, and excretion (ADME) analyses were conducted to obtain further insights into the binding sites and pharmacokinetics, respectively.

RESULTS

Application of α-mangostin (1-3 µM) hyperpolarized the resting membrane potential (RMP) of small-sized DRG neurons by increasing background K⁺ conductance and thereby inhibited action potential generation. At micromolar levels, α-mangostin activates TREK-1, TREK-2, or TRAAK, members of the two-pore domain K⁺ channel (K2P) family known to be involved in RMP formation in DRG neurons. Furthermore, capsaicin-induced TRPV1 currents were potently inhibited by α-mangostin (0.43 ± 0.27 µM), and partly suppressed tetrodotoxin-sensitive voltage-gated Na⁺ channel (Na_V) currents. MD simulation revealed that multiple oxygen atoms in α-mangostin may form stable hydrogen bonds with TREKs, TRAAK, TRPV1, and Na_V channels. In silico ADME tests suggested that α-mangostin may satisfy the drug-likeness properties without penetrating the blood-brain barrier.

CONCLUSION

The analgesic properties of α-mangostin might be mediated by the multi-target modulation of ion channels, including TREK/TRAAK activation, TRPV1 inhibition, and reduction of the tetrodotoxin-sensitive Na_V current. The findings suggest that the phytochemical can be a multi-ion channel-targeting drug and an alternative drug for effective pain management.

Garcinone-E exhibits anticancer effects in HeLa human cervical carcinoma cells mediated via programmed cell death, cell cycle arrest and suppression of cell migration and invasion

Xanthones are an important class of natural compounds bearing huge bioactivity profiles. Garcinone-E is one among most active xanthones showing potential anticancer activity against various human cancer cell lines. Therefore, the current study was performed to explore the anticancer potency of naturally occurring garcinone-E xanthone against human HeLa cervical cancer cells. The underlying mechanism of action was also tried to be explored via testifying its induction of programmed cell death, arrest of cell cycle, suppression of cell migration, cell invasion and cell adhesion. MTT assay was implemented to estimate the viability of HeLa cells after garcinone-E exposure and clonogenic assay was used to analyze the effect on clonogenic potential. Acridine orange/ethidium bromine (AO/EB) staining assay was performed for monitoring of programmed cell death along with western blotting. Flow cytometric studies were carried out to analyze cell cycle check points. Transwell chambers assays were carried out for studying the impact of garcinone-E on migration and invasion potency of HeLa cells. Western blotting was used to study the expressions of apoptosis linked proteins in HeLa cells. Results indicated that garcinone-E remarkably decreased the viability to minimum in HeLa cells in both dose and time-reliant manner. The clonogenic capacity of HeLa cells was efficiently reduced by garcinone exposure. AO/EB staining showed that the anti-viability action of garcinone-E was apoptosis allied which was supported by western blotting as well. The cell cycle check points study indicated cell cycle arrest at G2/M-phase. HeLa cell migration and invasion were reduced efficiently after being subjected to garcinone-E treatment in a dose reliant fashion. In conclusion, garcinone-E has a remarkable potential to act as anti-cervical cancer chemopreventive provided further in vivo studies are required.

Garcinia mangostana Linn displays antidepressant-like and pro-cognitive effects in a genetic animal model of depression: a bio-behavioral study in the Flinders Sensitive Line rat

There is abundant evidence for both disorganized redox balance and cognitive deficits in major depressive disorder (MDD). Garcinia mangostana Linn (GM) has anti-oxidant activity. We studied the antidepressant-like and pro-cognitive effects of raw GM rind in Flinders Sensitive Line (FSL) rats, a genetic model of depression, following acute and chronic treatment compared to a reference antidepressant, imipramine (IMI). The chemical composition of the GM extract was analysed for levels of α- and γ-mangostin. The acute dose-dependent effects of GM (50, 150 and 200 mg/kg po), IMI (20 mg/kg po) and vehicle were determined in the forced swim test (FST) in FSL rats, versus Flinders Resistant Line (FRL) control rats. Locomotor testing was conducted using the open field test (OFT). Using the most effective dose above coupled with behavioral testing in the FST and cognitive assessment in the novel object recognition test (nORT), a fixed dose 14-day treatment study of GM was performed and compared to IMI- (20 mg/kg/day) and vehicle-treated animals. Chronic treated animals were also assessed with respect to frontal cortex and hippocampal monoamine levels and accumulation of malondialdehyde. FSL rats showed significant cognitive deficits and depressive-like behavior, with disordered cortico-hippocampal 5-hydroxyindole acetic acid (5-HIAA) and noradrenaline (NA), as well as elevated hippocampal lipid peroxidation. Acute and chronic IMI treatment evoked pronounced antidepressant-like effects. Raw GM extract contained 117 mg/g and 11 mg/g α- and γ-mangostin, respectively, with acute GM demonstrating antidepressant-like effects at 50 mg/kg/day. Chronic GM (50 mg/kg/d) displayed significant antidepressant- and pro-cognitive effects, while demonstrating parity with IMI. Both behavioral and monoamine assessments suggest a more prominent serotonergic action for GM as opposed to a noradrenergic action for IMI, while both IMI and GM reversed hippocampal lipid peroxidation in FSL animals. Concluding, FSL rats present with cognitive deficits and depressive-like behaviors that are reversed by acute and chronic GM treatment, similar to that of IMI.

Garcinone E induces apoptosis and inhibits migration and invasion in ovarian cancer cells

Ovarian cancer remains the most lethal gynecological malignant tumor. In this study, 24 xanthones were isolated and identified from the pericarps of mangosteen (Garcinia mangostana), and their anti-proliferative activities were tested in ovarian cancer cells. Garcinone E (GE) was found to exhibit excellent anti-proliferative effects among the tested xanthones. It significantly inhibited the proliferation in HEY, A2780, and A2780/Taxol cells as evidenced by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, lactate dehydrogenase (LDH) release assay, Hoechst 33342 staining, annexin V/PI staining, and JC-1 staining. It induced endoplasmic reticulum (ER) stress and activated the protective inositol-requiring kinase (IRE)-1α pathway. Knocking down IRE-1α further activated the caspase cascade and caused an increase in cell death. Moreover, GE eliminated the migratory ability of HEY cells by reducing the expression of RhoA and Rac. It also blocked the invasion, which might be related to downregulation of matrix metalloproteinases (MMPs), i.e., MMP-9 and MMP-2, and upregulation of tissue inhibitors of metalloproteinase (TIMP) -1 and TIMP-2. In summary, GE exerts anticancer activities by inducing apoptosis and suppressing migration and invasion in ovarian cancer cells, which indicates its therapeutic potential for ovarian cancer.

Supplementation with a Polyphenol-Rich Extract, TensLess® , Attenuates Delayed Onset Muscle Soreness and Improves Muscle Recovery from Damages After Eccentric Exercise

High-intensity exercises are known to provoke delayed onset muscle soreness (DOMS). Delayed onset muscle soreness typically occurs within the first 24 h, peaks between 24 and 72 h, and can last as long as 5-7 days post-exercise. Delayed onset muscle soreness is a multifactorial process involving both mechanical and biochemical components, associated with clinical features that may limit range of motion, and athletes seek for effective recovery strategies to optimize future training sessions. TensLess^® is a food supplement developed to help manage post-exercise recovery. The supplement has been investigated on 13 recreationally active athletes of both sex, during a randomized, double-blind, and crossover clinical investigation, including a 3-week washout period. The clinical investigation was based on the study of TensLess^® effects for DOMS management and on the reduction of associated muscle damages following an eccentric exercise protocol. Supplementation with TensLess^® induced significant decrease in DOMS perception (-33%; p = 0.008) as of the first 24 h; this was significantly correlated with a lowered release of muscle damage-associated biomarkers, namely myoglobin, creatinine, and creatine kinase, for the whole length of the recovery period. Taken together, these positive results clearly indicate that post-exercise supplementation with TensLess^® may preserve myocytes and reduce soreness following eccentric exercise-induced damages, and, accordingly, significantly shorten muscle recovery. Copyright © 2017 John Wiley & Sons, Ltd.

Medicinal properties of mangosteen (Garcinia mangostana L.): A comprehensive update

Garcinia mangostana L. (Clusiaceae) is a tropical tree native to Southeast Asia known as mangosteen which fruits possess a distinctive and pleasant taste that has granted them the epithet of "queen of the fruits". The seeds and pericarps of the fruit have a long history of use in the traditional medicinal practices of the region, and beverages containing mangosteen pulp and pericarps are sold worldwide as nutritional supplements. The main phytochemicals present in the species are isoprenylated xanthones, a class of secondary metabolites with multiple reports of biological effects, such as antioxidant, pro-apoptotic, anti-proliferative, antinociceptive, anti-inflammatory, neuroprotective, hypoglycemic and anti-obesity. The diversity of actions displayed by mangosteen xanthones shows that these compounds target multiple signaling pathways involved in different pathologies, and place them as valuable sources for developing new drugs to treat chronic and degenerative diseases. This review article presents a comprehensive update of the toxicological findings on animal models, and the preclinical anticancer, analgesic, neuroprotective, antidiabetic and hypolipidemic effects of G. mangostana L. extracts and its main isolates. Pharmacokinetics, drug delivery systems and reports on dose-finding human trials are also examined.

Endogenous Opiates and Behavior: 2015

This paper is the thirty-eighth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2015 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia, stress and social status, tolerance and dependence, learning and memory, eating and drinking, drug abuse and alcohol, sexual activity and hormones, pregnancy, development and endocrinology, mental illness and mood, seizures and neurologic disorders, electrical-related activity and neurophysiology, general activity and locomotion, gastrointestinal, renal and hepatic functions, cardiovascular responses, respiration and thermoregulation, and immunological responses.