Bamboo leaf extract improves spatial learning ability in a rat model with senile dementia

The alleviative effects comparison of four flavonoids from bamboo leaves on ulcerative colitis in an Alzheimer mouse model

BACKGROUND

Clinically, patients with dementia are at high risk of developing enteritis, especially those with AD. This study explored the potential therapeutic benefits of bamboo leaf flavonoids (BLF) for ulcerative colitis (UC) treatment in Alzheimer's disease (AD) mouse model.

METHODS

Various methods were employed, including pathological staining of brain/colon tissue, inflammatory cytokine detection in serum, and oxidative stress indicator assessment to compare ulcerative enteritis (UC) injury in normal and AD mice and determine whether AD mice were susceptible to colitis. Then, the effects of BLF on UC and AD were investigated via several unique indices further to determine whether it alleviated colitis injury and possessed beneficial properties. Moreover, four main components of BLF were utilized to treat primary colon epithelial cells and neuron cells to compare their effects in alleviating inflammation and oxidation. Furthermore, homoorientin embedded with ursolic acid was detected by HPLC and the in vitro release simulation experiments of the nanoparticles were performed.

RESULTS

BLF complexes positively impacted ulcerative colitis by reducing disease activity, it also helped to reduce inflammation. Moreover, the BLF complexes decreased oxidative stress in the brain and colon tissues, indicating its potential as a neuroprotective agent. The flavonoid complexes reduced the expression levels of GFAP, Iba-1, and Aβ in the brain tissue, highlighting its role in attenuating neuroinflammation and AD pathology. Additionally, the embedded homoorientin coated with ursolic acid showed stronger bioactivities when compared with the uncoated group.

CONCLUSION

These results suggest that BLF complexes and its four main chemicals may be useful for treating AD- and UC-related complications, the embedded homoorientin coated with ursolic acid even demonstrated stronger bioavailability than homoorientin. Considering BLF complexes were verified to suppress the progressions of AD and UC for the first time, and the embedded homoorientin was never reported in published articles, the present study might provide a new perspective on its potential applications.

The neuroprotective effect of traditional Chinese medicinal plants-A critical review

Neurodegenerative and neuropsychiatric diseases are increasingly affecting individuals' quality of life, thus increasing their cost to social and health systems. These diseases have overlapping mechanisms, such as oxidative stress, protein aggregation, neuroinflammation, neurotransmission impairment, mitochondrial dysfunction, and excitotoxicity. Currently, there is no cure for neurodegenerative diseases, and the available therapies have adverse effects and low efficacy. For neuropsychiatric disorders, such as depression, the current therapies are not adequate to one-third of the patients, the so-called treatment-resistant patients. So, searching for new treatments is fundamental. Medicinal plants appear as a strong alternative and complement towards new treatment protocols, as they have been used for health purposes for thousands of years. Thus, the main goal of this review is to revisit the neuroprotective potential of some of the most predominant medicinal plants (and one fungus) used in traditional Chinese medicine (TCM), focusing on their proven mechanisms of action and their chemical compositions, to give clues on how they can be useful against neurodegeneration progression.

Bamboo leaf: A review of traditional medicinal property, phytochemistry, pharmacology, and purification technology

ETHNOPHARMACOLOGICAL RELEVANCE

Bamboos are perennial evergreen plants that belong to the subfamily Bambusoideae of the true grass family Poaceae, with more than thousands of species distributed around the world. They are used as a traditional medicine with demonstrated effects of anti-oxidation, free radical scavenging, anti-inflammatory, liver protection and ameliorating cognitive deficits. Bamboo leaf is mainly used for the treatment of atherosclerotic, diabetic and nervous system diseases.

AIM OF THE STUDY

This review aims to provide up-to-date information on the traditional medicinal properties, phytochemistry, pharmacology, and purification technologies of bamboo leaf.

MATERIALS AND METHODS

Relevant information on bamboo leaf was obtained by an online search of worldwide accepted scientific databases (Web of Science, ScienceDirect, Elsevier, SpringerLink, ACS Publications, Wiley Online Library and CNKI).

RESULTS

More than 100 chemical compounds, including flavonoids and flavonoid glycosides, volatile components, phenolic acids, polysaccharide, coenzyme Q10, phenylpropanoid and amino acids have been reported to be present. These compounds were usually extracted by column chromatography and membrane separation technologies. Preparative high performance liquid chromatography (PHPLC), high-speed counter-current chromatography (HSCCC), simulated moving bed chromatography (SMB) and dynamic axial compression chromatography (DAC) were the advanced separation technologies have been used to isolate C-glycosides from bamboo leaf flavonoid, the main bioactive ingredient of bamboo leaf. Currently, bamboo leaf is mainly used for the treatment of atherosclerotic, diabetic, hepatic diseases and nervous system related symptoms, which are attributed to the presence of bioactive components of bamboo leaf.

CONCLUSIONS

Phytochemical and pharmacological analyses of bamboo leaf have been revealed in recent studies. However, most of the pharmacological studies on bamboo leaf have focused on bamboo leaf flavonoids. Further studies need to pay more attention to other phytochemical components of bamboo leaf. In addition, there is lack of sufficient clinical data and toxicity studies on bamboo leaf. Therefore, more clinical and toxicity researches on this plant and constituents are recommended.

Protein phosphatase 2A activators reverse age-related behavioral changes by targeting neural cell senescence

The contribution of cellular senescence to the behavioral changes observed in the elderly remains elusive. Here, we observed that aging is associated with a decline in protein phosphatase 2A (PP2A) activity in the brains of zebrafish and mice. Moreover, drugs activating PP2A reversed age-related behavioral changes. We developed a transgenic zebrafish model to decrease PP2A activity in the brain through knockout of the ppp2r2c gene encoding a regulatory subunit of PP2A. Mutant fish exhibited the behavioral phenotype observed in old animals and premature accumulation of neural cells positive for markers of cellular senescence, including senescence-associated β-galactosidase, elevated levels cdkn2a/b, cdkn1a, senescence-associated secretory phenotype gene expression, and an increased level of DNA damage signaling. The behavioral and cell senescence phenotypes were reversed in mutant fish through treatment with the senolytic ABT263 or diverse PP2A activators as well as through cdkn1a or tp53 gene ablation. Senomorphic function of PP2A activators was demonstrated in mouse primary neural cells with downregulated Ppp2r2c. We conclude that PP2A reduction leads to neural cell senescence thereby contributing to age-related behavioral changes and that PP2A activators have senotherapeutic properties against deleterious behavioral effects of brain aging.

Effects of bamboo leaf extract on energy metabolism, antioxidant capacity, and biogenesis of small intestine mitochondria in broilers

The present study was carried out to investigate the effects of bamboo leaf extract (BLE) on energy metabolism, antioxidant capacity, and biogenesis of broilers' small intestine mitochondria. A total of 384 one-day-old male Arbor Acres broiler chicks were randomly divided into four groups with six replicates each for 42 d. The control group was fed a basal diet, whereas the BLE1, BLE2, and BLE3 groups consumed basal diets with 1.0, 2.0, and 4.0 g/kg of BLE, respectively. Some markers of mitochondrial energy metabolism including isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, and malate dehydrogenase and some markers of redox system including total superoxide dismutase, malondialdehyde, and glutathione were measured by commercial colorimetric kits. Mitochondrial and cellular antioxidant genes, mitochondrial biogenesis-related genes, and mitochondrial DNA copy number were measured by quantitative real-time-polymerase chain reaction (qRT-PCR). Data were analyzed using the SPSS 19.0, and differences were considered as significant at P < 0.05. BLE supplementation linearly increased jejunal mitochondrial isocitrate dehydrogenase (P < 0.05) and total superoxide dismutase (P < 0.05) activity. The ileal manganese superoxide dismutase mRNA expression was linearly affected by increased dietary BLE supplementation (P < 0.05). Increasing BLE supplementation linearly increased jejunal sirtuin 1 (P < 0.05) and nuclear respiratory factor 1 (P < 0.05) mRNA expression. Linear (P < 0.05) and quadratic (P < 0.05) responses of the ileal nuclear respiratory factor 2 mRNA expression occurred with increased dietary BLE levels. In conclusion, BLE supplementation was beneficial to the energy metabolism, antioxidant capacity, and biogenesis of small intestine mitochondria in broilers. The dose of 4.0 g/kg BLE demonstrated the best effects.

Effect of Withania somnifera (L.) Dunal aqueous root extract on reinstatement using conditioned place preference and brain GABA and dopamine levels in alcohol dependent animals

ETHNOPHARMACOLOGICAL RELEVANCE

Withania somnifera (L.) Dunal (WS), a known'Rasayana' (rejuvenating agent) as per Ayurveda is prescribed to promote health, to increase longevity and to hasten recovery in disease convalescent stages. WS has demonstrated protective effect on alcohol dependence and withdrawal anxiety in previous experimental studies.

AIM OF THE STUDY

To evaluate effect of WS on conditioned place behavioral paradigm (model of relapse) and on GABA and dopamine levels in critical brain areas in alcohol dependent animals.

METHODOLOGY

Following Animal Ethics Committee permission, the mice (n = 24) were divided into the following study groups for experiment 1: 1 -distilled water (vehicle control), 2 -WS and 3 -Naltrexone. They were conditioned on conditioned place preference (CPP) using alcohol (2 gm/kg)/saline (1 ml) administered intraperitoneally for 8 days. WS and Naltrexone were administered during the period of extinction (6-8 days). Effect of WS (650 mg/kg) on reinstating behaviour of mice (time spent in alcohol paired compartment) primed with alcohol injection was noted. In experiment 2, effect of WS (450 mg/kg/) on GABA and dopamine levels in the midbrain, striatum and cortex (ng/gm) were measured in alcohol dependent rats (n = 24) following the first phase of standardisation assay (n = 36). The rats were made alcohol dependent for 15 days (intermittent access model) and WS was administered concurrently. GABA and dopamine levels were measured on Day 16.

RESULTS

WS group showed decrease in time spent in alcohol paired compartment alike Naltrexone and it differed significantly compared to the distilled water control group (p < 0.05) Alcohol-dependent rats showed significant decrease in GABA and increase in dopamine levels vs distilled water in the midbrain, striatum and cortex. WS and Naltrexone administration showed rise in GABA and fall in dopamine in all the isolated brain parts in the respective groups (p < 0.05 vs alcohol treated group).

CONCLUSION

Withania somnifera protected animals from relapse and showed beneficial effects on the brain neurotransmitters involved in alcohol dependence. The study provides substantial evidence for its potential application in alcohol use disorder.

The Extract from Acidosasa longiligula Alleviates in vitro UV-Induced Skin Cell Damage via Positive Regulation of Thioredoxin 1

Introduction

Skin, as the outermost organ, is exposed to a wide range of environmental risk factors including ultraviolet (UV) and all kinds of pollutants. Excessive UV exposure contributes to many disorders, such as photoaging, skin inflammation, and carcinogenesis.

Methods

To determine the effects of bamboo extract (BEX) from our local plant, Acidosasa longiligula, on UV-irritated human skin, we conducted a variety of studies, including Western blot, apoptosis assays, reactive oxygen species (ROS) detection, and thioredoxin (TXN) and thioredoxin reductase (TXNRD) activity assays in primary skin keratinocytes.

Results

We first determined that BEX protects human skin keratinocytes against UV radiation-induced apoptosis and ROS production. UV radiation can robustly impair TXN and TXNRD activity which can, in turn, be significantly rescued by BEX treatment. Moreover, BEX regulates TXN1 levels in primary skin keratinocytes and TXN1 is proved to be required for the protective function of BEX. Last, we found that the NF-κB/p65 pathway mediates the protective function of BEX against UV.

Discussion

Collectively, our work delineates the beneficial role of BEX in UV-induced skin cell damage and provides a novel therapeutic reagent to prevent or alleviate the progress of photoaging and other UV-provoked skin diseases.

Sasa Quelpaertensis Nakai Induced Antidepressant-Like Effect in Ovariectomized Rats

Background

Sasa quelpaertensis Nakai extract (SQE) or dwarf bamboo has been extensively investigated for its antioxidant and anti-inflammatory effects; however, no previous study assessed its effect as an antidepressant agent. Therefore, this study was designed to examine the effect of oral SQE administration in ameliorating menopausal depressive symptoms and to evaluate its mechanisms in ovariectomized rats with repeated stress.

Methods

All experimental groups except normal group underwent ovariectomy and then immobilization for 14 consecutive days. During these 2 weeks, two rat groups received SQE (100 and 300 mg/kg orally) and their cutaneous body temperature was measured. The tail suspension test (TST) and forced swim test (FST) were performed in order to evaluate depression-like behavior. Additionally, enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry were carried out to evaluate the central monoaminergic neurotransmitter levels and activity.

Results

Oral SQE (100 mg/kg) administration had reduced immobility time in TST and FST. Additionally, the SQE 100 and 300 mg/kg administration had decreased the cutaneous body temperature in the rats compared to those without treatment. In ELISA analysis, the SQE 100 group expressed elevated levels of serotonin and dopamine in the hypothalamus, prefrontal cortex, and hippocampus. Antityrosine hydroxylase (anti-TH) antibodies showed a tremendous increase in the density of TH positive cells in the locus coeruleus (LC) region of the SQE 100 group. Likewise, the SQE 100 elevated the number of tryptophan hydroxylase (TPH) and protein kinase C (PKC) immunoreactive cell counts and density in the hypothalamic region.

Conclusion

These results suggested that the oral SQE administration induced the antidepressant-like effect in the ovariectomized rats with repeated stress via upregulating the levels of serotonin and dopamine through enhancing the expression of TH, TPH, and PKC in many brain areas.

Interhemispheric functional connectivity for Alzheimer's disease and amnestic mild cognitive impairment based on the triple network model

The purpose of this study was to explore the differences in interhemispheric functional connectivity in patients with Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) based on a triple network model consisting of the default mode network (DMN), salience network (SN), and executive control network (ECN). The technique of voxel-mirrored homotopic connectivity (VMHC) analysis was applied to explore the aberrant connectivity of all patients. The results showed that: (1) the statistically significant connections of interhemispheric brain regions included DMN-related brain regions (i.e. precuneus, calcarine, fusiform, cuneus, lingual gyrus, temporal inferior gyrus, and hippocampus), SN-related brain regions (i.e. frontoinsular cortex), and ECN-related brain regions (i.e. frontal middle gyrus and frontal inferior); (2) the precuneus and frontal middle gyrus in the AD group exhibited lower VMHC values than those in the aMCI and healthy control (HC) groups, but no significant difference was observed between the aMCI and HC groups; and (3) significant correlations were found between peak VMHC results from the precuneus and Mini Mental State Examination (MMSE) and Montreal Cognitive Scale (MOCA) scores and their factor scores in the AD, aMCI, and AD plus aMCI groups, and between the results from the frontal middle gyrus and MOCA factor scores in the aMCI group. These findings indicated that impaired interhemispheric functional connectivity was observed in AD and could be a sensitive neuroimaging biomarker for AD. More specifically, the DMN was inhibited, while the SN and ECN were excited. VMHC results were correlated with MMSE and MOCA scores, highlighting that VMHC could be a sensitive neuroimaging biomarker for AD and the progression from aMCI to AD.

Duration-dependent effect of exposure to static electric field on learning and memory ability in mice

With the rapid development of ultra-high-voltage direct-current (UHVDC) transmission, the strength of environmental static electric field (SEF) around UHVDC transmission lines increased substantially, which has aroused widely public attention on the potential health effects of SEF. In this study, the effect of SEF exposure on learning and memory ability was investigated. Institute of Cancer Research mice were exposed to 56.3 kV/m SEF for a short term (7 days) or long term (49 days). Behaviors in the Morris water maze (MWM) test, hippocampal neurotransmitter contents, and oxidative stress indicators were examined. Results showed that short-term SEF exposure significantly prolonged escape latency and decreased the number of platform-site crossovers, as well as decreased the time spent in the target quadrant in the MWM test. Meanwhile, serotonin level and the ratio of glutamate level to γ-aminobutyric acid level changed significantly. Besides, malondialdehyde content and glutathione peroxidase activity increased significantly, while superoxide dismutase activity decreased significantly. After long-term SEF exposure, all indices above showed no significant differences between the SEF and sham exposure groups. These data indicated that short-term exposure to 56.3 kV/m SEF could cause abnormal neurotransmitter levels and oxidative stress in the hippocampus, which led to the decline in learning and memory ability. Under the condition of long-term exposure, the SEF-induced disturbances in neurotransmitter contents and redox balance were offset by the compensatory responses of mice, and thus, the learning and memory ability returned to normal level. The temporary and reversible decline in learning and memory ability was only a common biological effect of SEF rather than a health hazard.