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Huperzine A (HupA) is used in Alzheimer's disease (AD) therapy for its effective inhibition of acetylcholinesterase (AChE) and enhancement of cholinergic neuronal function. However, direct oral administration and injection of HupA cause side effects like nausea, anorexia, and rapid metabolism. Using a tripolymer, poly(3-hydroxybutyrate- co -3-hydroxyvalerate-co-3-hydroxyhexanoate (PBVHx), from the polyhydroxyalkanoate (PHA) family synthesized via synthetic biology, we present a novel AD therapy strategy with peritoneally administered PBVHx microspheres loaded with HupA (HupA-PBVHxMs). This approach extends HupA's metabolic duration in the blood and brain, enhancing AChE inhibition efficacy. Uniformly sized HupA-PBVHxMs, created using microfluidics and rotary evaporation, show up to 70.4 % drug encapsulation efficiency, sustained HupA release for 40 days, reduced neurotoxicity from Aβ25–35, and maintained in vivo HupA supply and AChE inhibition for over 20 days. In cognitive tests, HupA-PBVHxMs improved function in AD mice. Thus, PBVHx microspheres with slower HupA release and lower biotoxicity offer a superior platform for sustained AChE inhibitor release, outperforming commercial PLGA microspheres. Based on a triopolymer, poly(3-hydroxybutyrate- co -3-hydroxyvalerate-co-3-hydroxyhexanoate (PBVHx), within the natural polyhydroxyalkanoate (PHA) family synthesized via a synthetic biology platform, we propose a novel approach for Alzheimer's disease (AD) therapy. This approach involves the peritoneal administration of PBVHx microspheres loaded with HupA (referred to as HupA-PBVHxMs) to significantly mitigate neurotoxicity induced by Aβ25–35 in vitro. Additionally, HupA-PBVHxMs sustains in vivo HupA supply and acetylcholinesterase (AChE) inhibition in both the blood and brain for over 20 days. [Display omitted] [ABSTRACT FROM AUTHOR]

Huperzine A (Hup A), an extract from Huperzia serrata, exerted its anti-inflammation and anti-oxidation effect to protect against neurodegenerative disorders and organ injury. Ferroptosis was indicated to involve in the development of acute lung injury (ALI) accompanying by lipid reactive oxygen species (ROS) overexpressed. However, there is little research focused on the protective effect of Hup A on ALI, and the underlying molecular mechanism remains elusive. This study aims to determine the therapeutic effect of Hup A on ALI in vivo and in vitro. Hup A attenuated lung injury and cellular damage in lipopolysaccharide-induced ALI (LPS-ALI) models, both in vivo and in vitro , accompanied by the upregulation of ferroptosis-associated proteins (SLC7A11 and GPX4). Furthermore, the pretreatment with Hup A decreased the abundance of inflammation factors (IL-6, TNF-α), MDA, lipid ROS, and Fe2+ in the LPS-ALI model, while it also promoted the secretion of SOD and GSH to antagonize peroxidation. Mechanistically, RNA sequencing and network pharmacological analysis synergistically revealed the PI3K/Akt signaling pathway as a potential target of Hup A. In vitro experiments demonstrated that Hup A effectively activated GPX4 through the PI3K/Akt signaling pathway, which was subsequently reversed by LY294002, an inhibitor of the PI3K/Akt signaling pathway. Consequently, our results revealed that Hup A inhibited ferroptosis in LPS-ALI by activating the PI3K-Akt signaling pathway which indicated the potential therapeutical effect of Hup A and further emphasized the pivotal role of ferroptosis in ALI. • The treatment of Hup A effectively ameliorated the LPS-ALI both in vivo and in vitro. • Hup A attenuated lipid ROS levels and conferred protection against ferroptosis. • Hup A inhibits ferroptosis in pulmonary epithelial cells of LPS-ALI by activating the PI3K-Akt signaling pathway. [ABSTRACT FROM AUTHOR]

[Display omitted] • HupA boosts survival from 20 % to 60 % via α7nAChR. • HupA reduces pro-inflammatory cytokine levels and oxidative stress via α7nAChR. • HupA ameliorates CLP-induced acute lung injury in mice via α7nAChR. • HupA modulates immune cell composition via α7nAChR. • HupA regulates intestinal flora homeostasis in CLP-induced sepsis mice via α7nAChR. • HupA involves the α7nAChR/protein kinase B/glycogen synthase kinase-3 pathways. Sepsis, characterized by high mortality rates, causes over 50 % of acute lung injury (ALI) cases, primarily due to the heightened susceptibility of the lungs during this condition. Suppression of the excessive inflammatory response is critical for improving the survival of patients with sepsis; nevertheless, no specific anti-sepsis drugs exist. Huperzine A (HupA) exhibits neuroprotective and anti-inflammatory properties; however, its underlying mechanisms and effects on sepsis-induced ALI have yet to be elucidated. In this study, we demonstrated the potential of HupA for treating sepsis and explored its mechanism of action. To investigate the in vivo impacts of HupA, a murine model of sepsis was induced through cecal ligation and puncture (CLP) in both wild-type (WT) and α7 nicotinic acetylcholine receptor (α7nAChR) knockout mice. Our results showed that HupA ameliorates sepsis-induced acute lung injury by activating the α7nAChR. We used the CLP sepsis model in wild-type and α7nAChR −/− mice and found that HupA significantly increased the survival rate through α7nAChR, reduced the pro-inflammatory cytokine levels and oxidative stress, ameliorated histopathological lung injury, altered the circulating immune cell composition, regulated gut microbiota, and promoted short-chain fatty acid production through α7nAChR in vivo. Additionally, HupA inhibited Toll-like receptor NF-κB signaling by upregulating the α7nAChR/protein kinase B/glycogen synthase kinase-3 pathways. Our data elucidate HupA's mechanism of action and support a "new use for an old drug" in treating sepsis. Our findings serve as a basis for further in vivo studies of this drug, followed by application to humans. Therefore, the findings have the potential to benefit patients with sepsis. [ABSTRACT FROM AUTHOR]

A series of C-3 arylated huperzine A (HPA) derivatives (1 − 30) were designed and synthesized in good yields via palladium-catalyzed Suzuki cross-coupling reaction. Cholinesterase inhibitory and neuroprotective activities of all 30 derivatives were evaluated. Cholinesterase inhibition results revealed that derivatives 2 and 15 exhibited dual inhibitory activity against both acetylcholinesterase (AChE inhibition: 2 , IC 50 = 1.205 ± 0.395 μ M; 15 , IC 50 = 0.225 ± 0.062 μ M) and butyrylcholinesterase (BChE inhibition: 2 , IC 50 = 8.598 ± 3.605 μ M; 15 , IC 50 = 4.013 ± 0.068 μ M), a feature not observed in huperzine A. Molecular docking results indicated that the introduction of aryl groups enhanced the affinity of the derivatives for the acyl-binding pocket of BChE, thereby limiting the hydrolysis of acetyl choline. However, these derivatives exhibited poor performance in cytotoxicity and neuroprotection assays. [Display omitted] • Thirty C-3 arylated huperzine A derivatives (1 – 30) were designed and synthesized via palladium-catalyzed Suzuki cross-coupling reaction. • Derivative 2 and 15 exhibited dual inhibition activity against both AChE and BChE. • A molecular docking study were performed to elucidate the interaction between these derivatives and BChE. [ABSTRACT FROM AUTHOR]

Huperzine A loaded multiparticulate tablet with sustained release was developed to reduce dosing frequency and increase swallowing. The sustained release was provided by the ethyl cellulose/Poloxamer 127 (EC/F127) microparticles (MPs). F127 was added to facilitate drug release of EC MPs, and the enhanced dissolution mechanism was investigated regarding to the particle size, water uptake, and wettability of MPs. The greater wettability, which highly relied on the medium and formulation components, generated larger water uptake and faster drug release through improving the penetration of the medium into the internal space of MPs. The EC/F127 MPs were further compressed into tablets for dissolution and pharmacokinetic studies. The results demonstrated that the tablet remained unchanged release profile to the MPs, and exhibited profoundly sustained release with a relatively bioavailability of 125.18% to the commercial tablet. Therefore, the multiparticulate tablet was successfully designed based on the drug release mechanism and high compressibility of MPs. Unlabelled Image • Microparticles (MPs) prepared by UPPS showed excellent flowability and compressibility. • In vitro and in vivo drug release profiles of MPs were maintained after compaction. • The Huperzine A loaded multiparticulate tablet showed sustained-release effect. [ABSTRACT FROM AUTHOR]

Huperzine A (HupA) is a kind of Lycopodium alkaloid with potential disease-modifying qualities that has been reported to protect against β-amyloid (Aβ)-mediated mitochondrial damage in Alzheimer's disease. However, the fundamental molecular mechanism underlying the protective action of HupA against Aβ-mediated mitochondrial malfunction is not completely understood. Recently, the mitochondrial enzyme amyloid-binding alcohol dehydrogenase (ABAD) protein has been reported to facilitate Aβ-induced mitochondrial damage, resulting in mitochondrial malfunction and cell death. Our study found that HupA, but not the acetylcholinesterase inhibitor tacrine, reduced the deposition of Aβ and the ABAD level, and further reduced Aβ–ABAD complexes, thereby improving cerebral mitochondrial function in APP/PS1 mice. This was accompanied by attenuated reactive oxygen species overload, as well as increases adenosine triphosphate levels. Moreover, HupA decreased the release of cytochrome-c from mitochondria and the level of cleaved caspase-3, thereby increasing dissociated brain cell viability in APP/PS1 mice. Thus, our study demonstrated that a reduction in ABAD was involved in the protective mechanism of HupA on the cerebral mitochondrial function in APP/PS1 mice. • Huperzine A (HupA) protected dissociated brain cell mitochondrial function by reducing amyloid-binding alcohol dehydrogenase level in APP/PS1 mice. • HupA could attenuate reactive oxygen species overload and increase adenosine triphosphate levels and membrane potential. • HupA decreased the level of amyloid-β–amyloid-binding alcohol dehydrogenase complexes. • HupA increase dissociated brain cells viability by reducing the cytoplasmic cyt c and cleaved caspase-3. [ABSTRACT FROM AUTHOR]

Abstract The club moss family Lycopodiaceae produces a diverse array of bioactive lycopodium alkaloids (LAs). In particular, the alkaloid huperzine A (hupA) has grasped attention since it is a potent acetylcholinesterase inhibitor of medical interest in Alzheimer's disease. Although the structural diversity and bioactivities of LAs have been studied to some extent, their chemotaxonomic value is mostly unexplored, especially to a lower taxonomic unit (e.g. subspecies or genotypes). This study focused on previously reported Icelandic Huperzia selago genotypes, and aimed to evaluate the chemotaxonomic value of LAs in resolving them. Using liquid chromatography-mass spectrometry (LC-MS), alkaloid fingerprints of H. selago taxa were subjected to principal component analysis (PCA). Our results revealed that each genotype tends to have its own alkaloid profile. Genotype 1 and 3 form distinct groups in a PCA plot, where genotype 2 is an intermediate between the other two genotypes. HupA and its derivative, huperzine B, both contribute to the differentiation of genotype 3 from the others. Therefore, our study demonstrated the potential of alkaloid fingerprints in resolving deep taxonomic groups and selecting plant taxa of medicinal importance. Graphical abstract Image 1 Highlights • Alkaloid fingerprinting of Icelandic Huperzia selago was performed using LC-MS. • A hidden diversity of lycopodane-type alkaloids is revealed in H. selago. • Principal component analysis shows genotype-specific groups. • Alkaloid fingerprinting could resolve club moss taxa at subspecies level. [ABSTRACT FROM AUTHOR]

Ultra-fine particle processing system (UPPS) was more advantageous in producing microparticles (MPs) than the conventional technologies since it was applicable for a wide range of drugs and the MPs could be manufactured in a successive and controllable way under mild conditions. The MPs based on this technology showed small uniform particle size, proper surface roughness, and dense structure, which were anticipated to benefit tablet compaction. Therefore, ethyl cellulose (EC) was selected as the matrix material to confirm the superiorities of UPPS produced MPs for compaction due to its rigidity and inflexibility. To improve the encapsulation efficiency (EE%) of EC based MPs, hydrophilic/hydrophobic plasticizers and polymers were added, and the effect was mechanistically investigated regarding to the polymer properties and particle size of MPs. The results revealed that the EE% of MPs was significantly improved in the presence of hydrophilic polymers, which was mainly related to the reduced drug leakage as a result of modified polymer properties and decreased particle size of MPs. The forming mechanism of MPs determined by X-ray photoelectron spectroscopy (XPS) revealed that the MPs were enriched with low molecular weight polymers on the surface due to the unevenly migration driven by the centrifugal force. The topography of MPs determined by atomic force microscopy showed that the MPs had considerable rough surface to the commercial excipient, which benefited for further compaction. Consequently, the dissolution profile of MPs after compaction was approachable to that of original MPs and the tablets showed optimal content uniformity. [ABSTRACT FROM AUTHOR]

Both drug-related cues and drug priming are the main factors that induce relapse of drug addiction. Previous research has reported that blockade of the muscarinic receptors could significantly depress addictive behavior, suggesting that the muscarinic receptors might be involved in drug use and relapse behavior. The nucleus accumbens (NAc), especially the shell of the NAc, where the muscarinic receptors are expressed, is critical for craving and relapse. This study investigated the effects of microinfusion of the muscarinic receptor antagonist scopolamine into the NAc shell on context- and morphine-induced expression of behavioral sensitization. Behavioral sensitization was established by exposure to 5 mg/kg morphine once daily for five consecutive days. Expression of behavioral sensitization was induced by saline challenge or 5 mg/kg morphine challenge. The results showed that: (a) the muscarinic receptor antagonist scopolamine (10.8 μg/rat) microinjected into the NAc shell blocked expression of conditional sensitization; (b) acetylcholinesterase inhibitor huperzine-A (0.5 and 0.1 μg/rat), but not scopolamine (10.8 μg/rat), microinjected into the NAc shell blocked morphine-induced expression of sensitization; and (c) pre-infusion of scopolamine (10.8 μg/rat) reversed the inhibitory effect of huperzine-A (0.5 μg/rat) on morphine-induced sensitization. Our findings suggest that muscarinic receptors in the NAc shell play different roles in context-induced and morphine-challenged expression of behavioral sensitization. [ABSTRACT FROM AUTHOR]

Huperzine A has been used for improving symptoms of Alzheimer's disease. Its cholinergic side effect is thought to be an exaggerated pharmacological outcome linked to its high brain or CNS concentrations. Although Huperzine A is brain penetrable, its interaction with efflux transporters (ABCB1 and ABCG2) has not been fully investigated. The aim of the present study was to characterize roles of ABCB1 and ABCG2 in the transmembrane transport of Huperzine A and identify a rate limiting step in its brain distribution. Data obtained from stably transfected MDCK II cells showed that Huperzine A is a substrate of ABCB1 but not ABCG2. ABCB1 inhibitors significantly inhibited ABCB1 mediated efflux of Huperzine A. In Abcb1a −/− mice, the brain to plasma concentration ratio of Huperzine A was significantly increased as compared to the wild type mice, while there were no obvious differences between the wild type and Abcg2 −/− mice. Taken together, the present study demonstrated that ABCB1 but not ABCG2 played a predominant role in the efflux of Huperzine A across BBB. The current finding is clinically relevant as changes in ABCB1 activity in the presence of ABCB1 inhibitors or genetic polymorphism may affect efficacy and safety of Huperzine A. [ABSTRACT FROM AUTHOR]

Aims Alzheimer's Disease (AD) is characterized by a loss of cognitive function and also the accumulation of β-amyloid peptide (βAP) in the brain parenchyma, which plays an important role in this disease. However, it is often also associated with the non-cognitive symptoms such as loss of muscle function (Inclusion-Body Myositis-IBM). Main methods Sprague-Dawley rats (13 weeks-n = 68) were randomly assigned into five groups: Group C: Control; Group D: d -galactose; Group O + D: Bilateral oophorectomy + d -galactose; Group O: Bilateral oophorectomy; Group O + D + H: Bilateral oophorectomy + d -galactose + Hup-A. Tissue fixation was performed with the perfusion method. The Compound Muscle Action Potential (CMAP) and mechanical muscle activity were recorded using the standard electro-biophysical techniques. Immune staining was performed with specific antibodies, and the pathological changes were examined. RNA was obtained from brain tissue samples with the Trizol Method. Then, the expression data of mature-miRNAs ( rno-miR-9-5p, rno-miR-29a-3p, rno-miR-106a-5p, rno-miR-107 and rno-miR-125a-3p ), which may be effective in AD, were taken with Real-Time PCR. Key findings Impairments occurred in behavioral tests of the rats in the O + D group. βAP accumulation and AChE activity increased significantly in the forebrain in the O + D group compared to the C group. It was seen that Huperzine-A (Hup-A) reduced AChE activity and destructed βAP accumulation. There was a significant decrease in the maximum contractile force at different frequencies in the O + D group and in the O group compared to the C group. Significance It was found that Hup-A contributed to the healing process in rats for damage occurring both in the brain and in the neuro-muscular system. [ABSTRACT FROM AUTHOR]

Post-stroke depression (PSD) is the most common mood disorder following a stroke, and is also the main factor limiting recovery and rehabilitation in stroke patients. The present study was aimed to investigate whether Huperzine A (HupA) has antidepressant-like activity in a rat model of PSD, which was developed by middle cerebral artery occlusion followed by an 18-day chronic unpredictable mild stress in conjunction with isolation rearing. The sucrose preference and forced swim tests were used to assess depression-like behavior. Neurological and cognitive functions following ischemia were evaluated by neurological evaluation, the beam-walking test, the forelimb grip force test, and the water maze test. Levels of norepinephrine (NE), dopamine (DA), and 5-hydroxytryptamine (5-HT) in the hippocampus and prefrontal cortex were assayed by high performance liquid chromatography. Western blot analysis was used to evaluate hippocampal expression of the 5-hydroxytryptamine 1A receptor (5-HT 1A R), cAMP response element binding (CREB), phosphorylated CREB (p-CREB) and brain-derived neurotrophic factor (BDNF). The results showed that treatment with HupA for 4 weeks ameliorated behavioral abnormalities and the impairment of neurological and cognitive functions in PSD rats. This was accompanied by the upregulated hippocampal expression of 5-HT 1A R, p-CREB and BDNF, and increased levels of NE, DA, and 5-HT in the hippocampus and prefrontal cortex. These findings suggest that HupA has antidepressant-like effect and can improve neurological and cognitive functions in PSD rats, which suggest its therapeutic potential for depression after stroke. [ABSTRACT FROM AUTHOR]

Huperzine A (Hup-A) is a poorly water-soluble drug with low oral bioavailability. A self-microemulsifying drug delivery system (SMEDDS) was used to enhance the oral bioavailability and lymphatic uptake and transport of Hup-A. A single-pass intestinal perfusion (SPIP) technique and a chylomicron flow-blocking approach were used to study its intestinal absorption, mesenteric lymph node distribution and intestinal lymphatic uptake. The value of the area under the plasma concentration–time curve (AUC) of Hup-A SMEDDS was significantly higher than that of a Hup-A suspension ( P <0.01). The absorption rate constant ( K a ) and the apparent permeability coefficient ( P app ) for Hup-A in different parts of the intestine suggested a passive transport mechanism, and the values of K a and P app of Hup-A SMEDDS in the ileum were much higher than those in other intestinal segments. The determination of Hup-A concentration in mesenteric lymph nodes can be used to explain the intestinal lymphatic absorption of Hup-A SMEDDS. For Hup-A SMEDDS, the values of AUC and maximum plasma concentration ( C max ) of the blocking model were significantly lower than those of the control model ( P <0.05). The proportion of lymphatic transport of Hup-A SMEDDS and Hup-A suspension were about 40% and 5%, respectively, suggesting that SMEDDS can significantly improve the intestinal lymphatic uptake and transport of Hup-A. [ABSTRACT FROM AUTHOR]

Lysine decarboxylation is the first biosynthetic step of Huperzine A (HupA). Six cDNAs encoding lysine decarboxylases (LDCs) were cloned from Huperzia serrata by degenerate PCR and rapid amplification of cDNA ends (RACE). One HsLDC isoform was functionally characterized as lysine decarboxylase. The HsLDC exhibited greatest catalytic efficiency ( k cat / K m , 2.11 s −1 mM −1 ) toward L-lysine in vitro among all reported plant-LDCs. Moreover, transient expression of the HsLDC in tobacco leaves specifically increased cadaverine content from zero to 0.75 mg per gram of dry mass. Additionally, a convenient and reliable method used to detect the two catalytic products was developed. With the novel method, the enzymatic products of HsLDC and HsCAO, namely cadaverine and 5-aminopentanal, respectively, were detected simultaneously both in assay with purified enzymes and in transgenic tobacco leaves. This work not only provides direct evidence of the first two-step in biosynthetic pathway of HupA in Huperzia serrata and paves the way for further elucidation of the pathway, but also enables engineering heterologous production of HupA. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most frequent cause of dementia. Besides cognitive deterioration, patients with AD are prone to seizures - more than 20% of patients diagnosed with AD experience at least one unprovoked seizure and up to 7% have recurrent seizures. Although available antiepileptic drugs (AEDs) may suppress seizures in patients with AD, they may also worsen cognitive dysfunction and increase the risk of falls. On the basis of preclinical studies, we hypothesize that Huperzine A (HupA), a safe and potent acetylcholinesterase (AChE) inhibitor with potentially disease-modifying qualities in AD, may have a realistic role as an anticonvulsant in AD. [ABSTRACT FROM AUTHOR]

Neuroinflammatory deregulation in the brain plays a crucial role in the pathogenesis of sepsis associated encephalopathy (SAE). Given the mounting evidence of anti-inflammatory and neuroprotective effects of the cholinergic nervous system, it is surprising that there is little information about its changes in the brain during sepsis. To elucidate the role of the cholinergic nervous system in SAE, hippocampal choline acetyltransferase, muscarinic acetylcholine receptor-1, acetylcholinesterase and acetylcholine were evaluated in LPS-induced sepsis rats. Expression of pro-inflammatory cytokines, neuronal apoptosis, and animal cognitive performance were also assessed. Furthermore, therapeutic effects of the acetylcholinesterase inhibitor Huperzine A (HupA) on the hippocampal cholinergic nervous function and neuroinflammation were evaluated. A deficiency of the cholinergic nervous function was revealed in SAE, accompanied with over-expressed pro-inflammatory cytokines, increase in neuronal apoptosis and brain cognitive impairment. HupA remarkably promoted the deficient cholinergic nervous function and attenuated the abnormal neuroinflammation in SAE, paralleled with the recovery of brain function. We suggest that the deficiency of the cholinergic nervous function and the abnormal neuroinflammation are synergistically implicated in the pathogenesis of SAE. Thus, HupA is a potential therapeutic candidate for SAE, as it improves the deficient cholinergic nervous function and exerts anti-inflammatory action. [ABSTRACT FROM AUTHOR]

Huperzine A (HupA) is a plant-derived lycopodium alkaloid used for the treatment of Alzheimer's disease due to its inhibition against acetylcholinesterase. Currently, industrial production of HupA relies primarily on direct extraction from Huperzia serrate , a perennial herbaceous plant. However, this strategy cannot satisfy the increasing demand for HupA due to scarcity of H. serrate whose growth is quite slow. Pathway engineering has emerged as a novel strategy for the production of HupA. Unfortunately, the biosynthesis mechanism of HupA has not been well documented. In this review, we summarize not only the methods for plant extraction and chemical synthesis but also state-of-the-art advances in biosynthesis of HupA, including synthetic pathways, key enzymes, and especially catalytic mechanisms. Overall, this review aims to provide valuable insights for complete biosynthesis of Hup A. [ABSTRACT FROM AUTHOR]

Huperzine A (HupA) is a naturally occurring compound found in the firmoss Huperzia serrata . While HupA is a potent acetylcholinesterase inhibitor, its full pharmacologic profile is incompletely described. Since previous works suggested a capacity for HupA to prophylax against seizures, we tested the HupA antiepileptic potential in pentylenetetrazole (PTZ) rat epilepsy model and explored its mechanism of action by spectral EEG analysis and by paired-pulse transcranial magnetic stimulation (ppTMS), a measure of GABA-mediated intracortical inhibition. We tested whether HupA suppresses seizures in the rat PTZ acute seizure model, and quantified latency to first myoclonus and to generalized tonic–clonic seizure, and spike frequency on EEG. Additionally, we measured power in the EEG gamma frequency band which is associated with GABAergic cortical interneuron activation. Then, as a step toward further examining the HupA antiepileptic mechanism of action, we tested long-interval intracortical inhibition (LICI) using ppTMS coupled with electromyography to assess whether HupA augments GABA-mediated paired-pulse inhibition of the motor evoked potential. We also tested whether the HupA effect on paired-pulse inhibition was central or peripheral by comparison of outcomes following administration of HupA or the peripheral acetylcholinesterase inhibitor pyridostigmine. We also tested whether the HupA effect was dependent on central muscarinic or GABA A receptors by co-administration of HupA and atropine or PTZ, respectively. In tests of antiepileptic potential, HupA suppressed seizures and epileptic spikes on EEG. Spectral EEG analysis also revealed enhanced gamma frequency band power with HupA treatment. By ppTMS we found that HupA increases intracortical inhibition and blocks PTZ-induced cortical excitation. Atropine co-administration with HupA did not alter HupA-induced intracortical inhibition suggesting independent of muscarinic acetylcholine receptors mechanism in this model. Last, pyridostigmine did not affect the ppTMS-measured cortical inhibition suggesting that HupA-induced effect is centrally-mediated. Our data support antiepileptic HupA applications, and suggest that such activity may be via enhancement of GABAergic intracortical inhibition. [ABSTRACT FROM AUTHOR]

The multimodal MRI and 1H MRS study was designed to provide a structural and neurochemical view of D-galactose induced rat brain degeneration and its treatment with huperzine A. The volume changes were captured using MRI focused on the hippocampal region and a neurochemical profile was obtained from the same area using in vivo localized 1H MRS, which was compared with in vitro 1H MRS hippocampal spectra at the high field after the animals were culled. At the four week point, we observed a small decrease in N-acetylaspartate/creatine (NAA/tCr), myo-inositol/creatine (mIns/tCr) and glutamine/creatine (Gln/tCr) in the group in which neurodegeneration was induced. At the eight week point, we found only slight but statistically significant decreases in NAA/tCr, mIns/tCr and glutamate/creatine (Glu/tCr) in this group in vivo. However, in the treated group, the decrease in NAA/tCr and Glu/tCr was much more pronounced compared to the D-gal group. In vitro 1H MRS analysis from rat hippocampal samples showed very similar changes in metabolites, which were also much more pronounced in the treated group. Neurodegeneration was also confirmed by a significant decrease in γ-aminobutyrate/creatine (GABA/tCr) observed only in the treated group, but not in the D-gal group. MRI image data and subsequent volumetric quantification showed mild hippocampal degeneration at the four week point in D-gal group. At the eight week point, we observed a decrease in hippocampal volume in both experimental groups, with a more pronounced decrease in the huperzine-treated group. In conclusion, in our experimental design huperzine A treatment worsened the neurodegeneration of the rat brain, which was supported by all of the used MRI and 1H MRS methods. • MRI found a reduction in hippocampal volumes in age-related dementia model in rats. • In vivo , in vitro MRS showed signs of neurodegeneration in the abovementioned model. • Huperzine aggravated neurodegeneration confirmed by in vivo , in vitro MRS and MRI. [ABSTRACT FROM AUTHOR]

Introduction Based on common pharmacodynamic mechanisms, recent efforts to develop second generation alternatives for organophosphate (OP) prophylaxis have expanded to include cholinesterase (ChE) inhibiting compounds traditionally approved for use in the treatment of Alzheimer’s disease (AD). The primary purpose of this study was to determine the extent to which low-dose huperzine A, galantamine, or donepezil selectively inhibited acetylcholinesterase (AChE) versus butyrylcholinesterase (BChE) activity in healthy adults and whether such inhibition impacted neurobehavioral performance. Methods In addition to hourly red blood cell cholinesterase sampling, neurobehavioral function was assessed before and after a single oral dose of huperzine A (100 or 200 μg), galantamine (4 or 8 mg), donepezil (2.5 or 5 mg), or placebo (n = 12 subjects per drug/dose). Results Compared to placebo, both dosages of huperzine A and galantamine inhibited circulating AChE but not BChE. With the exception of huperzine A (200 μg), which maintained declarative recall performance across sessions, compounds did not improve neurobehavioral performance. Some aspects of neurobehavioral performance correlated with AChE activity, although associations may have reflected time of day effects. Discussion Although huperzine A and galantamine significantly inhibited AChE (and likely increased central acetylcholine levels), neither compound improved neurobehavioral performance. The latter was likely due to ceiling effects in this young, healthy test population. Under conditions of reduced cholinergic activity (e.g., Alzheimer's disease), AChE inhibition (and corresponding maintenance of cholinergic tone) could potentially maintain/augment some aspects of neurobehavioral function. [ABSTRACT FROM AUTHOR]

Abstract: Background: Nowadays, hepatic ischemia reperfusion (HI/R) injury is regarded as a serious concern in clinical practices. Huperzine A (HupA) is an alkaloid isolated from the Chinese folk medicine huperzia serrate, which has possessed diverse pharmacological actions. Methods: A mouse model of HI/R was caused by clamping the hepatic artery, the hepatoportal vein, and the bile duct with a vascular clamp for 30 minutes followed by reperfusion for 6 hours under anesthesia. The sham group experienced the identical procedure without hepatic ischemia. The HupA group received an injection into the tail vein 5 minutes prior to HI/R at the doses of 167 and 500 μg/kg. The vehicle group was injected with physiological saline instead of HupA. The liver function was assessed by determinations of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities. Tissue levels of superoxide dismutase (SOD), catalase (CAT), malondiadehyde (MDA), and glutathione (GSH) were also measured spectrophotometrically. In addition, the activities of hepatic inflammatory mediators such as nuclear factor kappa B (NF-κB) p65, tumor necrosis factors-α (TNF-α, interleukin-1β (IL-1β) and IL-6 were also measured. Furthermore, the apoptotic damage was evaluated by measuring caspase-3 activity in hepatic tissues. Results: Treatment with HupA in mice at the doses of 167 and 500 μg/kg remarkably reduced serum ALT and AST activities in HupA-treated ischemic mice. Furthermore, HupA treatment could enhance the activities of hepatic tissue SOD, CAT, and GSH but decrease MDA tissue content. The activities of inflammatory cytokines including NF-κB p65, TNF-α, IL-1β and IL-6 were all decreased in ischemic mice treated with HupA. Colorimetric test results illustrated that a marked reduction of caspase-3 activity was found in the HupA-treated group compared with the vehicle group. Conclusion: Our present data suggest that HupA has a protective role against HI/R injury of mice and antioxidative, anti-inflammatory, and antiapoptotic actions are involved in its protection. [Copyright &y& Elsevier]

Abstract: Huperzine A (HupA), a natural inhibitor of acetylcholinesterase derived from a plant, is a licensed anti-Alzheimer's disease (AD) drug in China and a nutraceutical in the United States. In addition to acting as an acetylcholinesterase inhibitor, HupA possesses neuroprotective properties. However, the relevant mechanism is unknown. Here, we showed that the neuroprotective effect of HupA was derived from a novel action on brain iron regulation. HupA treatment reduced insoluble and soluble beta amyloid levels, ameliorated amyloid plaques formation, and hyperphosphorylated tau in the cortex and hippocampus of APPswe/PS1dE9 transgenic AD mice. Also, HupA decreased beta amyloid oligomers and amyloid precursor protein levels, and increased A Disintegrin And Metalloprotease Domain 10 (ADAM10) expression in these treated AD mice. However, these beneficial effects of HupA were largely abolished by feeding the animals with a high iron diet. In parallel, we found that HupA decreased iron content in the brain and demonstrated that HupA also has a role to reduce the expression of transferrin-receptor 1 as well as the transferrin-bound iron uptake in cultured neurons. The findings implied that reducing iron in the brain is a novel mechanism of HupA in the treatment of Alzheimer's disease. [Copyright &y& Elsevier]

Highlights: [•] Nicotine and huperzine A treatments are beneficial in a rat model of acetic acid-induced colitis. [•] The mechanism is inhibition of oxidant production and release of pro-inflammatory cytokines. [•] Data suggest the role of the “anti-inflammatory cholinergic pathway” in this inflammatory condition. [ABSTRACT FROM AUTHOR]

Abstract: A UPLC–MS method was developed for quantifying huperzine A (HupA), an anti-Alzheimer’s disease (AD) drug candidate from the traditional Chinese medicine Qian Ceng Ta (Huperzia serrata), in samples of 11 Huperzia genus plants. The highest content of HupA was found in Huperzia pinifolia. The accumulation of various Lycopodium alkaloids was monitored in these tissues using high resolution Q-IMS-TOFMS analysis. Tissue culture of various Huperzia species has been achieved and production of HupA has been confirmed in the callus of H. pinifolia. Furthermore, it was established that the major alkaloid produced by the naturally grown plant and the callus of H. pinifolia changed dramatically from HupA to nankakurine B. [Copyright &y& Elsevier]

Abstract: Huperzine A (Hup A) is a lycopodium alkaloid from Huperzia serrata, which has been used as a therapeutic agent in several neurological disorders. Despite the diverse pharmacological activities Hup A has, its role in hippocampal neurogenesis remains to be established. This study showed that Hup A not only promoted the proliferation of cultured mouse embryonic hippocampal neural stem cells (NSCs), but also increased the newly generated cells in the subgranular zone (SGZ) of the hippocampus in adult mice. Furthermore, the in vitro findings indicated that low concentrations of Hup A stimulated the proliferation of cultured NSCs, whereas extremely high concentration of it decreased the cell proliferation. Hup A activated mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) signaling pathway, which was a well-known regulator of biological processes including cell proliferation and differentiation. ERK inhibitor dramatically inhibited the proliferative effect of Hup A on NSCs. Administration of Hup A to adult mice significantly enhanced the cell proliferation in dentate gyrus of hippocampus, and increased the remaining newborn cells 4 weeks after the drug administration. Moreover, the newly generated BrdU+/NeuN+ neurons were also increased by Hup A treatment. These findings suggest a novel role of Hup A in neurogenesis and provide a new insight into its therapeutic effects in neurological disorders via a neurogenesis-related mechanism. [Copyright &y& Elsevier]

Abstract: Aims: The loss of cholinergic function in the central nervous system contributes significantly to the cognitive decline associated with advanced age and dementias. Huperzine A (HupA) is a selective inhibitor of acetylcholinesterase (AChE) and has been shown to significantly reduce cognitive impairment in animal models of dementia. Based on the importance of astrocytes in physiological and pathological brain activities, we investigated the effect of HupA and tacrine on S100B secretion in primary astrocyte cultures. S100B is an astrocyte-derived protein that has been proposed to be a marker of brain injury. Main methods: Primary astrocyte cultures were exposed to HupA, tacrine, cholinergic agonists, and S100B secretion was measured by enzyme-linked immunosorbent assay (ELISA) at 1 and 24h. Key findings: HupA, but not tacrine, at 100μM significantly increased S100B secretion in astrocyte cultures. Nicotine (at 100 and 1000μM) was able to stimulate S100B secretion in astrocyte cultures. Significance: Our data reinforce the idea that AChE inhibitors, particularly HupA, do not act exclusively on the acetylcholine balance. This effect of HupA could contribute to improve the cognitive deficit observed in patients, which are attributed to cholinergic dysfunction. In addition, for the first time, to our knowledge, these data indicate that S100B secretion can be modulated by nicotinic receptors, in addition to glutamate, dopamine and serotonin receptors. [Copyright &y& Elsevier]

Abstract: The purpose of the present investigation was to explore feasibility of nanocarrier based transdermal delivery of Huperzine A (HupA) for the treatment of Alzheimer''s disease. For this investigation, microemulsion (ME), solid lipid nanoparticles (SLNs), and nanostructured lipid carriers (NLCs) were formulated and characterized for physicochemical parameters. The pseudo-ternary phase diagrams for microemulsion region were developed using generally recognized as safe (GRAS) excipients. The SLNs and NLCs were prepared by microemulsion template technique. These nanodispersions were formulated into gels for transdermal application and evaluated for various physicochemical parameters. In vitro permeation profiles in rat skin exhibited zero-order kinetics. HupA loaded ME exhibited superior permeation than NLCs followed by SLNs and cumulative amount permeated after 24h was found to be 147.68±9.42μg/cm2, 129.11±32.76μg/cm2 and 10.74±0.68μg/cm2, respectively. Furthermore, optimized gels were subjected to primary skin irritation testing over a period of 48h and were found to be safe for skin application. In vivo efficacy tested in scopolamine induced amnesia model indicated significant improvement in cognitive function in mice group treated with developed nanocarrier based formulations as compared to the control group. [Copyright &y& Elsevier]

Abstract: Bis(12)-hupyridone (B12H), derived from the Chinese medicinal component huperzine A, was originally designed as a novel acetylcholinesterase (AChE) inhibitor. In this paper, we report that B12H (24-h pretreatment) effectively blocked glutamate-induced neuronal excitotoxicity in cerebellar granule neurons (CGNs). However, the huge discrepancy between the EC50 value and IC50 value of B12H, to protect against neuronal toxicity (0.09μM) and to block the NMDA receptor (21.8μM) respectively, suggests that the neuroprotection of B12H might be not primarily due to the blockade of the NMDA receptor. Pretreatment by specific antagonists of alpha7-nicotinic acetylcholine receptor (α7nAChR), but not muscarinic acetylcholine receptor (mAChR) or α4β2nAChR, decreased the neuroprotection of B12H. The neuroprotection of B12H could also be abolished by the pretreatment of specific PI3-K inhibitors. Furthermore, B12H restored the suppressed activation of the Akt pathway caused by glutamate as evidenced by the decreased expressions of pSer473-Akt and pSer9-GSK3β. All these results suggest that B12H substantially protected CGNs against glutamate-induced neuronal excitotoxicity via activating α7nAChR/PI3-K/Akt cascade. [Copyright &y& Elsevier]

Abstract: The neuropathologic mechanisms after exposure to lethal doses of nerve agent are complex and involve multiple biochemical pathways. Effective treatment requires drugs that can simultaneously protect by reversible binding to the acetylcholinesterase (AChE) and blocking cascades of seizure related brain damage, inflammation, neuronal degeneration as well as promoting induction of neuroregeneration. [−]-Huperzine A ([−]-Hup A), is a naturally occurring potent reversible AChE inhibitor that penetrates the blood–brain barrier. It also has several neuroprotective effects including modification of beta-amyloid peptide, reduction of oxidative stress, anti-inflammatory, anti-apoptotic and induction and regulation of nerve growth factor. Toxicities at higher doses restrict the neuroporotective ability of [−]-Hup A for treatment. The synthetic stereoisomer, [+]-Hup A, is less toxic due to poor AChE inhibition and is suitable for both pre-/post-exposure treatments of nerve agent toxicity. [+]-Hup A block the N-methyl-d-aspartate (NMDA)-induced seizure in rats, reduce excitatory amino acid induced neurotoxicity and also prevent soman induced toxicity with minimum performance decrement. Unique combinations of two stereo-isomers of Hup A may provide an excellent pre/post-treatment drug for the nerve agent induced seizure/status epilepticus. We investigated a combination of [+]-Hup A with a small dose of [−]-Hup A ([+] and [−]-Hup A) against soman toxicity. Our data showed that pretreatment with a combination [+] and [−]-Hup A significantly increased the survival rate and reduced behavioral abnormalities after exposure to 1.2×LD50 soman compared to [+]-Hup A in guinea pigs. In addition, [+] and [−]-Hup A pretreatment inhibited the development of high power of EEG better than [+]-Hup A pretreatment alone. These data suggest that a combination of [+] and [−]-Hup A offers better protection than [+]-Hup A and serves as a potent medical countermeasure against lethal dose nerve agent toxicity in guinea pigs. [Copyright &y& Elsevier]

Abstract: Chemical warfare nerve agents such as soman exert their toxic effects through an irreversible inhibition of acetylcholinesterase (AChE) and subsequently glutamatergic function, leading to uncontrolled seizures. The natural alkaloid (−)-huperzine A is a potent inhibitor of AChE and has been demonstrated to exert neuroprotection at an appropriate dose. It is hypothesized that analogs of both (+)- and (−)-huperzine A with an improved ability to interact with NMDA receptors together with reduced AChE inhibition will exhibit more effective neuroprotection against nerve agents. In this manuscript, the tested huperzine A analogs 2 and 3 were demonstrated to improve survival of guinea pigs exposed to soman at either 1.2 or 2×LD50. [Copyright &y& Elsevier]

Abstract: Four series of novel heterodimers comprised of donepezil and huperzine A (HupA) fragments were designed, synthesized, and evaluated in search of potent acetylcholinesterase (AChE) inhibitors as potential therapeutic treatment for Alzheimer’s disease. Heterodimers comprised of dimethoxyindanone (from donepezil), hupyridone (from HupA), and connected with a multimethylene linker, were identified as potent and selective inhibitors of AChE. Diastereomeric heterodimers ( RS , S )-17b (with a tetramethylene linker) exhibited the highest potency of inhibition towards AChE with an IC50 value of 9nM and no detectable inhibitory effect on butyrylcholinesterase at 1mM. [Copyright &y& Elsevier]

Abstract: Huperzine A, a Lycopodium alkaloid produced by Chinese folk herb Huperzia serrata (Lycopodiaceae), has been shown to be a promising agent for the treatment of Alzheimer''s disease due to its potent acetylcholinesterase (AChE) activity, as well its efficacy in the treatment of memory of aged patients. Thus, the effects of two Huperzia species of habitats in Brazil (H. quadrifariata and H. reflexa) with described in vitro AChE inhibition activities were studied and their effects on mice brain AChE inhibition were determined after a single intraperitoneal (i.p.) injection. The alkaloid extracts were administered to mice in various doses (10, 1 and 0.5mg/kg) and acetylcholinesterase activity was measured post mortem in two brain areas using the Ellman''s colorimetric method. The AChE activity was found to be significantly reduced in both the cortex and hippocampus, although this activity was less potent than that of reference inhibitor huperzine A (0.5mg/kg). Thus, it appears that H. quadrifariata and H. reflexa alkaloid extracts, shown to inhibit acetylcholinesterase in vitro, also have very potent in vivo effects, suggesting that the Huperzia species may still constitute a promising source of compounds with pharmaceutical interest for Alzheimer''s disease. [Copyright &y& Elsevier]

Abstract: Vascular dementia (VaD) is a common dementing illness. There are no pharmacological agents with a regulatory approval for its treatment or prevention. Review of published clinical trial reports indicates that early treatment of hypertension, a risk factor for stroke, reduces VaD risk and slows progression. However, unlike stroke, treatment of hyperlipidemia with statin class drugs or treatment of blood clotting abnormalities with acetylsalicylic acid do not appear to have an effect on VaD incidence or progression. Pharmacological agents for treatment of Alzheimer''s dementia (AD) such as memantine or acetylcholinesterase inhibitors have small positive effects on cognition in VaD, which are likely due to their action on co-existing AD-related neuropathology. Drug development efforts using novel approaches such as patient stratification by their genotype are needed in order to address the increasing need for effective VaD therapeutics. [Copyright &y& Elsevier]

Abstract: Huperzine A (HupA) and Huperzine B (HupB) are natural alkaloids existed in Lycopodium plants. They both have potential clinical application for treating Alzheimer''s Disease (AD). For the purpose of better utilizing the limited plant resources, a quick and low cost method to separate and purify HupA and HupB from Huperzia serrata (Thunb. ex Murray) was established in this paper. Low polarity macroporous resin SP850 was selected from eight kinds of resins during initial purification. Trifluoroacetic acid (TFA) was proved to be the best acid modifier reagent among all acids used in our experiment for improving separation. HupA and HupB were baseline separated on a C18 column by preparative high performance liquid chromatography (Preparative HPLC), the optimal gradient mobile phase system contained methanol increasing from 15% (v/v) to 35% (v/v) and 0.1% (v/v) TFA within the water. The purity of HupA and HupB obtained was 99.1% and 98.6%, respectively, and the total recovery for them was 83.0% and 81.8%, respectively. [Copyright &y& Elsevier]

Abstract: The huperzine A–phospholipid complex loaded biodegradable thermosensitive PLGA–PEG–PLGA polymer gel was studied as injectable implant system for controlled release of huperzine-A (HA). First, HA molecules were successfully incorporated into the soybean phosphatidylcholine (SP) molecules to form the huperzine-A–soybean phosphatidylcholine complexes (HA–SPC), which was proved by FT-IR, DSC, XRD, solubility study, TEM, etc. The results indicated that hydrogen bonds and electrostatic interaction between HA and SP molecules play an important role in the formation of HA–SPC. Secondly, the HA–SPC was loaded into biodegradable PLGA–PEG–PLGA thermosensitive gel as injectable implant material to control the release of HA. The in vitro and in vivo drug release behaviors of the prepared products were studied. The in vitro release studies demonstrated that the HA–SPC-loaded gel significantly reduced the initial burst of drug release and extended the release period to about 2 weeks. The in vivo pharmacokinetics study of HA–SPC-loaded gel in rabbits showed that plasma concentration of HA (2.54–0.15ng/mL) was detected for nearly 2 weeks from delivery systems upon single subcutaneous injection. What''s more, the in vitro release pattern correlated well with the in vivo pharmacokinetics profile. The present study indicates that HA–SPC loaded PLGA–PEG–PLGA thermal gel may be an attractive candidate vehicle for controlled HA release. [Copyright &y& Elsevier]

Abstract: A target-oriented highly enantioselective multifunctional organocatalytic approach has been developed to construct the bicycle-[3.3.1]nona-2,6-dien-9-one core of (−)-huperzine A for the first time, with up to 95% ee in the gram-scale procedure. The newly established methodology is also eligible to synthesize a variety of bicyclo[3.3.1]nona-2,6-dien-9-ones in high enantiopurities, and thus is useful for the future development of novel huperzine A analogs with medicinal interests. [Copyright &y& Elsevier]

Abstract: The cause of many neurodegenerative disorders can be ascribed to the loss of functional neurons, and thus agents capable of promoting neuronal differentiation may have therapeutic benefits to patients of these disorders. In this study, the effects and underlying mechanisms of bis(12)-hupyridone (B12H), a novel dimeric acetylcholinesterase inhibitor modified from huperzine A (HA), on neuronal differentiation were investigated using both the rat PC12 pheochromocytoma cell line and adult rat hippocampus neural stem cells. B12H (3–30μM), characterized by morphological changes and expression of GAP-43, induced neurite outgrowth in a concentration- and time-dependent manner, with almost 3-fold higher efficacy than that of HA in PC12 cells. Furthermore, B12H (2.5–10μM), but not HA, promoted neuronal differentiation as shown by the percentage increase of βIII-tubulin positive neurons in neural stem cells. The activities of extracellular signal-regulated kinase (ERK), as well as its downstream transcription factors Elk-1 and cAMP response element-binding protein (CREB) were elevated in the B12H-treated PC12 cells. Mitogen-activated protein kinase kinase inhibitors and alpha7-nicotinic acetylcholine receptor (α7nAChR) antagonist blocked the neurite outgrowth and the activation of ERK induced by B12H. All these findings suggest that B12H potently induces pro-neuronal cells into differentiated neurons by activating the ERK pathway possibly via regulating α7nAChR. These findings support the recent proposition that α7nAChR is required for the neuronal dendritic arborization and differentiation in the adult mice hippocampus, and provide insights into the possible therapeutic potential of B12H in treating neurodegenerative disorders. [Copyright &y& Elsevier]

Abstract: Cognitive enhancing substances such as amphetamine and modafinil have become popular in recent years to improve acute cognitive performance particularly in environments in which enhanced cognition or intelligence is required. Nutraceutical nootropics, which are natural substances that have the ability to bring about acute or chronic changes in cognition have also been gaining popularity in a range of settings and applications including the workplace, driving and in the amelioration of age related cognitive decline. Huperzine A, Vinpocetine, Acetyl-l-carnitine, Rhodiola Rosea and Alpha-lipoic Acid are popular nutritional supplements that have shown promising benefits in improving a range of biological (e.g., blood flow, anti-inflammatory, anti-oxidant, and direct neurotransmitter effects) and cognitive processes from in vitro, animal and human clinical research. We report here the first human randomized clinical trial for cognition in which we administer a combination of Huperzine A, Vinpocetine, Acetyl-l-carnitine, R. Rosea and Alpha-lipoic acid (called Ceretrophin) vs placebo. Sixty participants (40 females and 20 males, with a mean age of 45.4years, SD=12.6) completed either the odd or even items from the Raven Advanced Progressive Matrices (APM) at baseline and the opposite odd or even items at week 4 after consuming either the combination nootropic or placebo. A significant study visit (time)×treatment condition interaction was found: F (1, 57)=7.279, p=0.009, partial η2 =.113, with paired samples t-tests revealing a significant improvement in mean APM score from baseline to retest (week 4) (t(34)=−4.045, p<.001) for the Ceretrophin™ group. Improvements in APM scores could be attributed to the active intervention over the placebo, indicating that the treatment improved general intelligence. Implications for improving our understanding of the biological basis of intelligence and pharmacologically improving human cognition are discussed. [Copyright &y& Elsevier]

Abstract: Binding energy calculations of huperzine A (HUP A) and galanthamine (GAL) to the binding pocket of the acetylcholinesterase enzyme (AChE) were studied. It was found that hydrogen bond formation and particular hydrogen π interactions exhibit the most significant contributions to the binding interaction of HUP A with Trp84 (W84) and Tyr130 (Y130), whereas no hydrogen bond was detected with Y130 of GAL binding. The interaction energies, calculated at the MP2 level between drugs and residues, demonstrate that the attractive interactions between GAL and residues at positions 84 and 130 were less than those for HUP A by 1.6 and 7.7 kcal·mol–1, respectively. In addition, ONIOM3 results show that the binding energies of HUP A per pocket (–28.4 kcal mol–1) are higher than for GAL per pocket (–17.0 kcal·mol–1). The detailed understanding of these interactions can be useful for the design of specific inhibitors for the AChE binding site. From the Clinical Editor: The more efficient and specific inhibition of acetylcholinesterase may provide an enhanced treatment strategy in Alzheimer’s disease compared to the currently available inhibitors. This study discusses interactions of the enzyme binding site with two ligands. The results may pave the way to the development of more potent inhibitors. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, whether coadministration of huperzine A (HA) and ligustrazine phosphate (LP) could effectively improve the memory deficits in association with ameliorating cholinergic impairment and oxidative stress in the scopolamine-induced amnesia rats was assessed. The effects of treatment with Coa [HA (0.14mg/kg, i.g.) and LP (110mg/kg, i.g.)] on amnesia were investigated in Morris water maze. Furthermore, the effects on the activities of acetylcholinesterase (AChE) and antioxidant enzymes within the cerebral cortex and hippocampus were evaluated, and the lipid peroxidation product malondialdehyde (MDA) was also analyzed. As a result, coadministration of HA and LP for 10 consecutive days could markedly reverse the scopolamine-induced learning and memory impairment determined by the Morris water maze test. Moreover, AChE activity was significantly inhibited, and superoxide dismutases (SOD) and glutathione peroxidase (GSH-Px) activities were significantly increased with a remarkable reduction in the level of MDA. In conclusion, coadministration of HA and LP effectively prevented cholinergic impairment and oxidative damage, thereby resulting in improvement of spatial learning memory in rats induced by scopolamine. The results suggested that coadministration of HA and LP might offer a novel poly-therapeutic drug regimen for preventing Alzheimer''s disease (AD). [Copyright &y& Elsevier]

Abstract: A new photoisomer of the promising “anti-Alzheimer” drug candidate (±) huperzine A is described. The new substance was formed via a photoisomerization reaction and was found to be 1-amino-13-ethylidene-11-methyl-6-aza-tetracyclo-[7.3.1.02.7.04.7]-trideca-2,10-diene-5-one using NMR analysis. The kinetics of its formation was studied and proven to be of first-order. The described photoisomer showed a significant loss in activity, being more than 100 times less active than (−) huperzine A itself. The new substance was named photohuperzine A, referring to its photopyridone substructure. [Copyright &y& Elsevier]

Abstract: Our previous work in cells and animals showed that mitochondria are involved in the neuroprotective effect of huperzine A (HupA). In this study, the effects of HupA on isolated rat brain mitochondria were investigated. In addition to inhibiting the Aβ25-35 (40 μM)-induced decrease in mitochondrial respiration, adenosine 5′-triphosphate (ATP) synthesis, enzyme activity, and transmembrane potential, HupA (0.01 or 0.1 μM) effectively prevented Aβ-induced mitochondrial swelling, reactive oxygen species increase, and cytochrome c release. More interestingly, administration of HupA to isolated mitochondria promoted the rate of ATP production and blocked mitochondrial swelling caused by normal osmosis. These results indicate that HupA protects mitochondria against Aβ at least in part by preserving membrane integrity and improving energy metabolism. These direct effects on mitochondria further extend the noncholinergic functions of HupA. [Copyright &y& Elsevier]

Summary: Botanicals and herbs have a centuries-old tradition of use by persons with epilepsy, in many cultures around the world. At present, herbal therapies are tried by patients in developing as well as developed countries for control of seizures or adverse effects from antiepileptic drugs (AEDs), or for general health maintenance, usually without the knowledge of physicians who prescribe their AEDs. Well-designed clinical trials of herbal therapies in patients with epilepsy are scarce, and methodological issues prevent any conclusions of their efficacy or safety in this population. Furthermore, some botanicals and herbs may be proconvulsant or may alter AED metabolism. In spite of these limitations, further preclinical evaluation of botanicals and herbs and their constituent compounds using validated scientific methods is warranted based on numerous anecdotal observations of clinical benefit in patients with epilepsy and published reports showing mechanisms of action relevant to epilepsy or anticonvulsant effects in animal models of epilepsy. This review highlights the use of herbal therapies for epilepsy, outlines the role of the U.S. Food and Drug Administration in regulating herbal products, and presents the author''s approach to the scientific assessment of herbal therapies as potential therapies for patients with epilepsy. [Copyright &y& Elsevier]

Abstract: Huperzine A (HupA), a novel Lycopodium alkaloid isolated from Chinese folk medicine Huperzia serrata (Qian Ceng Ta), is a potent, selective and well-tolerated inhibitor of acetylcholinesterase (AChE). It has been proven to significantly improve the learning and memory impairment in Alzheimer''s disease (AD) and vascular dementia (VaD) patients in China. Interestingly, our recent data indicate that HupA also possesses other protective functions. This paper will give an overview on the protective effects of HupA, which includes regulating β-amyloid precursor protein (APP) metabolism, protecting against Aβ-mediated oxidative stress, apoptosis and mitochondrial dysfunction, as well as anti-inflammation. The multiple neuroprotective effects of HupA might yield additional beneficial effects in AD and VaD therapy. [Copyright &y& Elsevier]

Abstract: As part of a phase Ib clinical trial to determine the tolerability and safety of the highly specific acetylcholinesterase (AChE) inhibitor huperzine A, twelve (12) healthy elderly individuals received an escalating dose regimen of huperzine A (100, 200, 300, and 400μg doses, twice daily for a week at each dose), with three (3) individuals as controls receiving a placebo. Using the WRAIR whole blood cholinesterase assay, red blood cell AChE and plasma butyrylcholinesterase (BChE) were measured in unprocessed whole blood samples from the volunteers following each dose, and then for up to 48h following the final and highest (400μg) dose to monitor the profile of inhibition and recovery of AChE. Significant inhibition of AChE was observed, ranging from 30–40% after 100μg to >50% at 400μg, and peaking 1.5h after the last dose. Gradual recovery of AChE activity then occurs, but even 48h after the last dose red blood cell AChE was about 10% below control (pre-dose) values. Huperzine A levels in plasma peaked 1.5h after the final 400μg dose (5.47±2.15ng/mL). Plasma BChE was unaffected by huperzine A treatment (as expected). Aliquots of huperzine A-containing (from three individuals) and placebo blood samples were exposed ex vivo to the irreversible nerve agent soman (GD) for 10min, followed by removal of unbound huperzine and soman from the blood by passing through a small C18 reverse phase spin column. Eluted blood was diluted in buffer, and aliquots taken at various time intervals for AChE and BChE activity measurement to determine the time taken to achieve full return in activity of the free enzyme (dissociation from the active site of AChE by huperzine A), and thus the proportion of AChE that can be protected from soman exposure. Huperzine A-inhibited red blood cell (RBC) AChE activity was restored almost to the level that was initially inhibited by the drug. The increased doses of huperzine A used were well tolerated by these patients and in this ex vivo study sequestered more red blood cell AChE than has been previously demonstrated for pyridostigmine bromide (PB), indicating the potential improved prophylaxis against organophosphate (OP) poisoning. [Copyright &y& Elsevier]

Abstract: Alzheimer’s disease (AD) is growing in impact on human health. With no known cure, AD is one of the most expensive diseases in the world to treat. Huperzine A (HupA), a anti-AD drug candidate from the traditional Chinese medicine Qian Ceng Ta (Huperzia serrata), has been shown to be a powerful and selective inhibitor of acetylcholinesterase and has attracted widespread attention because of its unique pharmacological activities and low toxicity. As a result, HupA is becoming an important lead compound for drugs to treat AD. HupA is obtained naturally from very limited and slowly growing natural resources, members of the Huperziaceae. Unfortunately, the content of HupA is very low in the raw plant material. This has led to strong interest in developing sources of HupA. We have developed a method to propagate in vitro tissues of Phlegmariurus squarrosus, a member of the Huperziaceae, that produce high levels of HupA. The in vitro propagated tissues produce even higher levels of HupA than the natural plant, and may represent an excellent source for HupA. [Copyright &y& Elsevier]

Abstract: Comparison of single and multiple dose pharmacokinetics between patches and conventional tablets of Huperzine A (Hup-A) was performed in beagle dogs to evaluate the patches’ controlled drug release characteristics in vivo, a newly developed transdermal system for treatment of Alzheimer disease. Results showed that transdermal administration of Hup-A prolonged T max value (24h vs. 3h, P <0.01), lowered C max value (3.4±0.2ngmL−1 vs. 9.8±1.0ngmL−1, P <0.01), and produced a relatively constant serum concentration within 84h after a single transdermal dose of 4mg/20cm2 Hup-A patches. Following application of the patches, Hup-A serum concentrations increased for approximately 12–24h, reaching an average C max of 3.4±0.2ngmL−1. Thereafter, a serum concentration of at least 2.1ngmL−1 was maintained for up to 84h. The serum concentration was maintained within the range of 2.4–4.3ngmL−1 during 2-week wearing period after multiple dosing, and the degree of fluctuation at the steady state of td and po administration was significantly different (0.51 vs. 1.99, P <0.01). This study indicates that Hup-A patches exhibited good controlled-release properties in vivo, maintained a relatively constant serum concentration within 3.5 d after wearing, and are suitable for twice-weekly application. [Copyright &y& Elsevier]

Abstract: Alpha-secretase (α-secretase), cleaves the amyloid precursor protein (APP) within the amyloid-β (Aβ) sequence, resulting in the release of a secreted fragment of APP (αAPPs) and precluding Aβ generation. We investigated the effects of the acetylcholinesterase inhibitor, huperzine A (Hup A), on APP processing and Aβ generation in human neuroblastoma SK-N-SH cells overexpressing wild-type human APP695. Hup A dose-dependently (0–10 μM) increased αAPPs release. Therefore, we evaluated two α-secretase candidates, a disintegrin and metalloprotease (ADAM) 10 and ADAM17 in Hup A-induced non-amyloidogenic APP metabolism. Hup A enhanced the level of ADAM10, and the inhibitor of tumor necrosis factor-α converting enzyme (TACE)/ADAM17 inhibited the Hup A–induced rise in αAPPs levels, further suggesting Hup A directed APP metabolism toward the non-amyloidogenic α-secretase pathway. Hup A had no effect on Aβ generation in this cell line. The steady-state levels of full-length APP and cell viability were unaffected by Hup A. Alpha-APPs release induced by Hup A treatment was significantly reduced by muscarinic acetylcholine receptor antagonists (particularly by an M1 antagonist), protein kinase C (PKC) inhibitors, GF109203X and calphostin C, and the mitogen-activated kinase kinase (MEK) inhibitors, U0126 and PD98059. Furthermore, Hup A markedly increased the phosphorylation of p44/p42 mitogen-activated protein (MAP) kinase, which was blocked by treatment with U0126 and PD98059. In addition, Hup A inhibited acetylcholinesterase activity by 20% in neuroblastoma cells. Our results indicate that the activation of muscarinic acetylcholine receptors, PKC and MAP kinase may be involved in Hup A–induced αAPPs secretion in neuroblastoma cells and suggest multiple pharmacological mechanisms of Hup A regarding the treatment of Alzheimer’s disease (AD). [Copyright &y& Elsevier]

Abstract: Huperzine A (HupA), isolated originally from a traditional Chinese medicine Qiang Ceng Ta, whole plant of Huperzia serrata (Thunb. ex Murray) Trev., a member of the Huperziaceae family, has attracted intense attention since its marked anticholinesterase activity was discovered by Chinese scientists. Several members of the Huperziaceae (Huperzia and Phlegmariurus species) have been used as medicines in China for contusions, strains, swellings, schizophrenia, myasthenia gravis and organophosphate poisoning. HupA has been marketed in China as a new drug for Alzheimer''s disease (AD) treatment and its derivative ZT-1 is being developed as anti-AD new drug candidate both in China and in Europe. A review of the chemistry, bioactivities, toxicology, clinical trials and natural resources of HupA source plants is presented. [Copyright &y& Elsevier]

Abstract: This paper presents to investigate the levels of Huperzine A in plasma and CSF of rats after three different kinds of administrations and to find out whether intranasal administration is the best root to transfer the drug into the CNS. The drugs of two doses (167 and 500μg/kg) were administered to male Sprague–Dawley rats intravenously, intranasally and intragastricly, respectively. Series plasma and cerebrospinal fluid (CSF) samples were collected from femoral artery and cisterna magna for 6h. The drug concentrations were determined by HPLC-fluorescence method. The AUCplasma and the AUCCSF of intranasal administration were 90.3% and 127.7% in low dose group (167μg/kg) and 91.3% and 69.4% in high dose group (500μg/kg) compared with intravenous administration. The AUCplasma and the AUCCSF of intragastric administration were 98.9% and 52.1% in high dose group (500μg/kg) compared with intravenous administration. [Copyright &y& Elsevier]