PAP 9704, a Korean Herbal Medicine Attenuates Methamphetamine-Induced Hyperlocomotion via Adenosine A2A Receptor Stimulation in Mice

In Vitro Effects of Dehydrotrametenolic Acid on Skin Barrier Function

Dehydrotrametenolic acid (DTA) is a lanostane-type triterpene acid isolated from Poria cocos Wolf (Polyporaceae). Several studies have reported the anti-inflammatory and antidiabetic effects of DTA; however, its effects on the skin are poorly understood. In this study, we investigated the effects of DTA on skin barrier function in vitro and its regulatory mechanism in human keratinocyte cell line HaCaT cells. DTA increased the microRNA (mRNA) expression of natural moisturizing factor-related genes, such as HAS-2, HAS-3, and AQP3 in HaCaT cells. DTA also upregulated the mRNA expression of various keratinocyte differentiation markers, including TGM-1, involucrin, and caspase-14. Moreover, the protein expression of HAS-2, HAS-3, and TGM-2 were significantly increased by DTA. To examine the regulatory mechanisms of DTA, Western blotting, luciferase-reporter assays, and RT-PCR were conducted. The phosphorylation of mitogen-activated protein kinases (MAPKs) and IκBα were increased in DTA-treated HaCaT cells. In addition, AP-1 and NF-κB transcriptional factors were dose-dependently activated by DTA. Taken together, our in vitro mechanism studies indicate that the regulatory effects of DTA on skin hydration and keratinocyte differentiation are mediated by the MAPK/AP-1 and IκBα/NF-κB pathways. In addition, DTA could be a promising ingredient in cosmetics for moisturizing and increased skin barrier function.

The Role of Adenosine Receptors in Psychostimulant Addiction

Adenosine receptors (AR) are a family of G-protein coupled receptors, comprised of four members, named A1, A2A, A2B, and A3 receptors, found widely distributed in almost all human body tissues and organs. To date, they are known to participate in a large variety of physiopathological responses, which include vasodilation, pain, and inflammation. In particular, in the central nervous system (CNS), adenosine acts as a neuromodulator, exerting different functions depending on the type of AR and consequent cellular signaling involved. In terms of molecular pathways and second messengers involved, A1 and A3 receptors inhibit adenylyl cyclase (AC), through Gi/o proteins, while A2A and A2B receptors stimulate it through Gs proteins. In the CNS, A1 receptors are widely distributed in the cortex, hippocampus, and cerebellum, A2A receptors are localized mainly in the striatum and olfactory bulb, while A2B and A3 receptors are found at low levels of expression. In addition, AR are able to form heteromers, both among themselves (e.g., A1/A2A), as well as with other subtypes (e.g., A2A/D2), opening a whole range of possibilities in the field of the pharmacology of AR. Nowadays, we know that adenosine, by acting on adenosine A1 and A2A receptors, is known to antagonistically modulate dopaminergic neurotransmission and therefore reward systems, being A1 receptors colocalized in heteromeric complexes with D1 receptors, and A2A receptors with D2 receptors. This review documents the present state of knowledge of the contribution of AR, particularly A1 and A2A, to psychostimulants-mediated effects, including locomotor activity, discrimination, seeking and reward, and discuss their therapeutic relevance to psychostimulant addiction. Studies presented in this review reinforce the potential of A1 agonists as an effective strategy to counteract psychostimulant-induced effects. Furthermore, different experimental data support the hypothesis that A2A/D2 heterodimers are partly responsible for the psychomotor and reinforcing effects of psychostimulant drugs, such as cocaine and amphetamine, and the stimulation of A2A receptor is proposed as a potential therapeutic target for the treatment of drug addiction. The overall analysis of presented data provide evidence that excitatory modulation of A1 and A2A receptors constitute promising tools to counteract psychostimulants addiction.

Cognitive-enhancing effects of hydrolysate of polygalasaponin in SAMP8 mice

OBJECTIVES

The aim of the study is to evaluate the cognitive-enhancing effects of hydrolysate of polygalasaponin (HPS) on senescence accelerate mouse P8 (SAMP8) mice, an effective Alzheimer's disease (AD) model, and to research the relevant mechanisms.

METHODS

The cognitive-enhancing effects of HPS on SAMP8 mice were assessed using Morris water maze (MWM) and step-through passive avoidance tests. Then N-methyl-D-aspartate (NMDA) receptor subunit expression for both the cortex and hippocampus of mice was observed using Western blotting.

RESULTS

HPS (25 and 50 mg/kg) improved the escape rate and decreased the escape latency and time spent in the target quadrant for the SAMP8 mice in the MWM after oral administration of HPS for 10 d. Moreover, it decreased error times in the passive avoidance tests. Western blotting showed that HPS was able to reverse the levels of NMDAR1 and NMDAR2B expression in the cortex or hippocampus of model mice.

CONCLUSIONS

The present study suggested that HPS can improve cognitive deficits in SAMP8 mice, and this mechanism might be associated with NMDA receptor (NMDAR)-related pathways.

Cardioprotective effect of rhizomes of Acorus gramineus against isoproterenol-induced cardiac damage in pigs

The present study was designed to evaluate the cardioprotective potential of water extract of rhizomes of Acorus gramineus (AGR) against isoproterenol (ISO)-induced myocardial infarction. Male pigs were orally administered with 250 or 500 mg/kg of AGR or with vehicle for 9 days, with concurrent subcutaneous injections of ISO on the 8th and 9th day. Administration of AGR significantly ameliorated ISO-induced cardiac dysfunctions as evidenced by the ventricular ST-segment interval and R-amplitude as well as the left ventricle fractional shortening and ejection fraction. Additionally, administration of AGR significantly attenuated increased cardiac injury markers, such as cardiac troponin T, tumor necrosis factor-α, and myeloperoxidase activity, and cardiac marker enzymes, and prevented the depletion of antioxidant parameters. Malondialdehyde formation was also inhibited by AGR. Based on the results, it is concluded that AGR possesses significant cardioprotective potential and may serve as an adjunct in the treatment and prophylaxis of myocardial infarction.

Traditional Chinese medicine in the treatment of ADHD: a review

This review covers an introduction of traditional Chinese medicine (TCM) in treating attention-deficit/hyperactivity disorder (ADHD), focusing on the traditional theoretic basis from the perspective of TCM regarding ADHD's cause, pathogenesis, methods of syndrome differentiation, and rationale for treatment. The authors present commonly accepted and successfully practiced clinical procedures used in China for diagnosis and treatment of ADHD by TCM clinicians along with the supportive clinical evidence. The authors hope to inspire more research to better understand the mechanisms underlying the therapies and to promote appropriate incorporation of TCM therapies with Western pharmacologic treatment to better help patients with ADHD.

Acorus gramineus inhibits microglia mediated neuroinflammation and prevents neurotoxicity in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of Parkinson's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Acorus gramineus Solander (Acoraceae, AG), is a widely distributed plant in Asian countries. Rhizome part of this plant has long been used as a traditional medicine for treating various symptoms including central nervous system (CNS) disorders.

AIM OF STUDY

The anti-neuroinflammatory effect of AG aqueous extract was investigated using in vitro cellular and in vivo Parkinson's disease (PD) mouse model.

MATERIALS AND METHODS

Lipopolysaccharide (LPS) is used to stimulate BV-2 microglial cells in vitro and the changes in neuroinflammatory expressional levels were measured using ELISA, Western blotting, RT-PCR and immunofluorescence techniques. In in vivo experiments, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxicated mouse model of PD was developed followed by immunohistochemical analysis of specific brain tissues.

RESULTS

LPS-stimulation to BV-2 cells increased the production of nitric oxide (NO) and proinflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β. Pretreatment with AG extract inhibited the increased levels of NO and pro-inflammatory cytokines in LPS-stimulated BV-2 cells. Mechanistic study revealed that AG acts via the regulation of nuclear factor kappa B (NF-κB), mitogen-activated protein kinases (MAPKs) and TRIF-dependent signaling pathways. Further, AG protected MPTP-induced neuronal cell death and inhibited neuroinflammation in vivo.

CONCLUSION

Our results indicated that AG extract exerted anti-neuroinflammatory effects against activated microglia mediated insults through multiple signaling pathways and prevented in vivo neuronal cell death in mouse model of PD substantiating the traditional claims for its use in CNS disorders.

Cognitive-enhancing effects of polygalasaponin hydrolysate in aβ(25-35)-induced amnesic mice

Polygalasaponins are the major active constituents of Polygala tenuifolia exhibiting antiamnesic activity, but their applications are limited due to their toxicities. Evidence showed that the toxicities can be attenuated by hydrolysis. Herein, effects of a hydrolysate of polygalasaponins (HPS) on cognitive impairment induced by Aβ₂₅₋₃₅ were assessed by Morris water maze and step-through passive avoidance tests. The impaired spatial reference memory was improved by HPS (50 and 100 mg/kg). In the acquisition trial of step-through test, HPS (50 and 100 mg/kg) increased the latency into the dark chamber and decreased the error frequency significantly (P < .05). However, no significant change was observed during the retention trial. Additionally, HPS increased the corresponding SOD activities (62.34%, 22.09%) and decreased MDA levels (28.21%, 32.35%) in both cortex and hippocampus as compared to model animals. These results show that HPS may be a useful treatment against amnesia probably via its antioxidant properties.

Antinociceptive properties of coumarins, steroid and dihydrostyryl-2-pyrones from Polygala sabulosa (Polygalaceae) in mice

We have investigated the possible antinociceptive action of the extract, fractions and pure compounds obtained from the whole plant Polygala sabulosa A. W. Bennett (Polygalaceae) in acetic acid-induced visceral pain in mice. Intraperitoneal injection of animals with the hydroalcoholic extract and fractions (CH2Cl2, EtOAc, n-BuOH, aqueous fraction) (1–100 mg kg−1) caused a dose-related and significant inhibition of the acetic acid-induced visceral nociceptive response. The CH2Cl2, EtOAc and n-BuOH fractions were more potent than the hydroalcoholic extract and aqueous fraction. The isolated compounds dihydrostyryl-2-pyrones (1, 2, 3), styryl-2-pyrone (7), α-spinasterol (9), scopoletin (10) and two esters of the coumarin (scopoletin) obtained semisynthetically, acetylscopoletin (10a) and benzoylscopoletin (10b) (0.001–10 mg kg−1), exhibited significant and dose-related antinociceptive effects against acetic acid-induced visceral pain. The results distinguished, for the first time, the extract, fractions and pure compounds obtained from P. sabulosa that produced marked antinociception against the acetic acid-induced visceral nociceptive response, supporting the ethnomedical use of P. sabulosa.

Dehydrotrametenolic acid selectively inhibits the growth of H-ras transformed rat2 cells and induces apoptosis through caspase-3 pathway

The screening of natural products that preferentially inhibit growth of H-ras transformed rat2 cells vs. rat2 cells was performed to identify H-ras specific growth inhibitor. A lanostane-type triterpene acid, dehydrotrametenolic acid (3beta-hydroxylanosta-7,9(11),24-trien-21-oic acid), was isolated from the sclerotium of Poria cocos (Polyporaceae). Dehydrotrametenolic acid selectively inhibited the growth of H-ras transformed cells with a GI(50) value of 40 microM. FACS analysis indicated that the compound exerted its anti-proliferation effects through cell cycle arrest at G2/M phase and accumulation of sub-G1 population. Dehydrotrametenolic acid-induced apoptosis was further confirmed with chromosomal DNA fragmentation, caspase-3 activation, and degradation of PARP and Lamin A/C degradation. The compound also regulated the expression of H-ras, Akt and Erk, which are the downstream proteins of H-ras signaling pathways. The results suggest that dehydrotrametenolic acid can be a potential anticancer agent against H-ras transformed tumor.