In vitro simulated saliva, gastric, and intestinal digestion followed by faecal fermentation reveals a potential modulatory activity of Epimedium on human gut microbiota.

Herba Epimedii, known for its rich array of bioactive ingredients and widespread use in ethnopharmacological practices, still lacks a comprehensive understanding of its gastrointestinal biotransformation. In this study, we qualitatively explored the dynamic changes in Epimedium sagittatum components during in vitro simulated digestions, with a quantitative focus on its five major flavonoids. Notably, significant metabolism of E. sagittatum constituents occurred in the simulated small intestinal fluid and colonic fermentation stages, yielding various low molecular weight metabolites. Flavonoids like kaempferol glycosides were fully metabolized in the simulated intestinal fluid, while hyperoside digestion occurred during simulated colon digestion. Colonic fermentation led to the production of two known bioactive isoflavones, genistein, and daidzein. The content and bioaccessibility of the five major epimedium flavonoids-icariin, epimedin A, epimedin B, epimedin C, and baohuoside I-significantly increased after intestinal digestion. During colon fermentation, these components gradually decreased but remained incompletely metabolized after 72 h. Faecal samples after E. sagittatum fermentation exhibited shift towards dominance by Lactobacillus (Firmicutes), Bifidobacterium (Actinobacteria), Streptococcus (Firmicutes), and Dialister (Firmicutes). These findings enhance our comprehension of diverse stages of Herba Epimedii constituents in the gut, suggesting that the primary constituents become bioaccessible in the colon, where new bioactive compounds may emerge.

Ultra-Long Cycle of Prussian Blue Analogs Achieved by Equilibrium Electrolyte for Aqueous Sodium-Ion Batteries.

Aqueous sodium-ion batteries have promising prospects in large-scale electrical energy storage, which lack of suitable cathode with high specific capacity and long cycle lifespan, unfortunately. Manganese-based Prussian blue analogs (PBAs) (KMnHCF/NaMnHCF) are ideal candidates for low-cost and high theoretical specific capacity merits. But the rapid decline hinders their application, due to side reactions caused by water imbalance. Here, an equilibrium strategy, which can balance the interstitial water supplement and water attack, is proposed. As proof of the concept, xCS (x: proportion, CS: co-solvent, such as polyethylene glycol and trimethyl phosphate) equilibrium electrolytes are introduced to solve the rapid decline. Assisting with the electrolyte, KMnHCF realizes excellent performance (10 000 cycles), which is beyond most cathode materials of sodium-ion batteries. The full batteries composed of KMnHCF cathode and NaTi2 (PO4 )3 anode also display outstanding performance (7000 cycles) and promising application prospects at low-temperature and engineering scenes. And then, the equilibrium electrolyte concept is verified by NaMn0.8 Fe0.2 HCF and NaMnHCF, proving its universality for low-cost and long-life manganese based PBAs.

Two new cytochalasins from the endophytic fungus Xylaria sp. GDGJ-77B.

Two new open-chain cytochalasins, xylarchalasins A and B (1 and 2), together with six known analogues (3-8), were isolated from the endophytic fungus Xylaria sp. GDGJ-77B from the Chinese medicinal plant Sophora tonkinensis. Their structures were elucidated on the basis of comprehensive spectroscopic analysis. Compound 2 displayed moderate antibacterial activities against Bacillus subtilis and Escherichia coli with MIC values of 25 and 12.5 µg/mL, respectively.

Asiatic Acid Alleviates Myocardial Ischemia-Reperfusion Injury by Inhibiting the ROS-Mediated Mitochondria-Dependent Apoptosis Pathway.

Myocardial ischemia-reperfusion injury (MIRI) is a major cause of heart failure in patients with coronary heart disease (CHD). Mitochondrial dysfunction is the crucial factor of MIRI; oxidative stress caused by mitochondrial reactive oxygen species (ROS) aggravates myocardial cell damage through the mitochondria-dependent apoptosis pathway. Asiatic acid (AA) is a type of pentacyclic triterpene compound purified from the traditional Chinese medicine Centella asiatica, and its protective pharmacological activities have been reported in various disease models. This study is aimed at investigating the protective effects of AA and the underlying mechanisms in MIRI. To achieve this goal, an animal model of MIRI in vivo and a cell model of oxygen-glucose deprivation/reperfusion (OGD/R) in vitro were established. The results show that AA exerts a protective effect on MIRI by improving cardiac function and reducing cardiomyocyte damage. Due to its antioxidant properties, AA alleviates mitochondrial oxidative stress, as evidenced by the stable mitochondrial structure, maintained mitochondrial membrane potential (MMP), and reduced ROS generation, otherwise due to its antiapoptotic properties. AA inhibits the mitogen-activated protein kinase (MAPK)/mitochondria-dependent apoptosis pathway, as evidenced by the limited phosphorylation of p38-MAPK and JNK-MAPK, balanced proportion of Bcl-2/Bax, reduced cytochrome c release, inhibition of caspase cascade, and reduced apoptosis. In conclusion, our study confirms that AA exerts cardiac-protective effects by regulating ROS-induced oxidative stress via the MAPK/mitochondria-dependent apoptosis pathway; the results provide new evidence that AA may represent a potential treatment for CHD patients.

HPLC-DAD Fingerprints Combined With Multivariate Analysis of Epimedii Folium From Major Producing Areas in Eastern Asia: Effect of Geographical Origin and Species.

The growth location and plant variety may influence the active components and biological activities of plants used in phytomedicine. In this study, nine sets of different Epimedii Folium, from different representative cultivation locations and Epimedium species, were collected for comparison, using HPLC-DAD combined with multivariate analysis. The objective was to investigate the influence of geographical origin and Epimedium species on the quality of Epimedii Folium, and provide applicable guidance for cultivation and quality control of Epimedii Folium. Several Epimedium spp. sets were used to establish the HPLC-DAD fingerprints and 91 peaks (compounds) were selected for the multivariate analysis. Major compounds were analyzed by HPLC-DAD combined with principal component analysis (PCA). HPLC quantitative analysis of known bioactive compounds was performed. Application of PCA to HPLC data showed that Epimedium samples sharing the same geographical origin or species clustered together, indicating that both species and geographical origin have impacts on the quality of Epimedii Folium. The major bioactive flavonoid compounds, epimedin C, icariin and baohuoside I, were identified and quantified. The concentration of bioactive compounds was significantly influenced both by species and geographical origin. E. sagittatum from Sichuan showed the highest content of bioactive compounds. The results showed that both Epimedium species and geographical origin have strong impact into quality of Epimedii Folium. HPLC data combined with multivariate analysis is a suitable approach to inform the selection of cultivation areas and choose Epimedium spp. most suitable for different geographical areas, resulting in improved quality of Epimedii Folium.

Supplementation with γ-glutamylcysteine (γ-GC) lessens oxidative stress, brain inflammation and amyloid pathology and improves spatial memory in a murine model of AD.

INTRODUCTION: The accumulation of oxidative stress, neuroinflammation and abnormal aggregation of amyloid ß-peptide (Aß) have been shown to induce synaptic dysfunction and memory deficits in Alzheimer's disease (AD). Cellular depletion of the major endogenous antioxidant Glutathione (GSH) has been linked to cognitive decline and the development of AD pathology. Supplementation with γ-glutamylcysteine (γ-GC), the immediate precursor and the limiting substrate for GSH biosynthesis, can transiently augment cellular GSH levels by bypassing the regulation of GSH homeostasis. METHODS: In the present study, we investigated the effect of dietary supplementation of γ-GC on oxidative stress and Aß pathology in the brains of APP/PS1 mice. The APP/PS1 mice were fed γ-GC from 3 months of age with biomarkers of apoptosis and cell death, oxidative stress, neuroinflammation and Aß load being assessed at 6 months of age. RESULTS: Our data showed that supplementation with γ-GC lowered the levels of brain lipid peroxidation, protein carbonyls and apoptosis, increased both total GSH and the glutathione/glutathione disulphide (GSH/GSSG) ratio and replenished ATP and the activities of the antioxidant enzymes (superoxide dismutase (SOD), catalase, glutamine synthetase and glutathione peroxidase (GPX)), the latter being a key regulator of ferroptosis. Brain Aß load was lower and acetylcholinesterase (AChE) activity was markedly improved compared to APP/PS1 mice fed a standard chow diet. Alteration in brain cytokine levels and matrix metalloproteinase enzymes MMP-2 and MMP-9 suggested that γ-GC may lower inflammation and enhance Aß plaque clearance in vivo. Spatial memory was also improved by γ-GC as determined using the Morris water maze. CONCLUSION: Our data collectively suggested that supplementation with γ-GC may represent a novel strategy for the treatment and/or prevention of cognitive impairment and neurodegeneration.

[DuzhongButiansu Capsules improve adenine-induced reproductive dysfunction in male rats].

OBJECTIVE: To study the effect of DuzhongButiansu Capsules (DBC) on adenine-induced reproductive dysfunction (RD) in male rats. METHODS: Eighty male SD rats were randomly divided into six groups, blank control (n = 8), solvent control (n = 8), RD model control (n = 16), Shengjing Capsules (SJC) (n = 16), low-dose DBC (n = 16) and high-dose DBC (n = 16). The RD model was made by intragastric administration of adenine at 200 mg/kg/d for 5 successive weeks in the latter four groups of animals, and in the meantime the rats in the latter three groups were treated intragastrically with SJC at 0.560 mg/kg/d and DBC at 0.242 and 0.968 mg/kg/d, respectively. At the end of the fourth week, all the rats were mated with female ones in a 1:1 ratio for 7 days. Then the male rats were killed and the right epididymides collected for detection of sperm concentration and motility, and the female ones sacrificed after fed for another 2 weeks and the numbers of pregnancies and fetal rats were recorded. The heart, liver, spleen, lung, kidney, thymus, testis, epididymis and seminal vesicle were harvested for obtainment of the visceral coefficients and semen parameters, observation of the histopathological changes in the testis, epididymis and kidneys by HE staining, measurement of the levels of serum T, E2, FSH and LH by ELISA, detection of the contents of serum glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), malondialdehyde (MDA) and creatinine (Scr), blood urea nitrogen (BUN), and determination of the expressions of Bax, Bcl-2, Caspase-3 and Caspase-9 proteins in the renal tissue by immunohistochemistry. RESULTS: No statistically significant difference was observed between the blank control and solvent control groups in any of the indexes obtained (P > 0.05).Compared with the blank controls, the rats in the RD model control group showed significantly decreased sperm concentration (ï¼»40.67 ± 7.37ï¼½vs ï¼»27.10 ± 2.72ï¼½ ×106/ml, P < 0.01), sperm motility (ï¼»54.75 ± 3.92ï¼½%vs ï¼»25.60 ± 4.83ï¼½%, P < 0.01) and pregnancy rate (85.7% vs 43.8%, P < 0.01). The rats in thelow- and high-dose DBCgroups exhibited remarkable increases in sperm concentration (ï¼»53.00 ± 4.55ï¼½% and ï¼»65.63 ± 12.47ï¼½% ×106/ml, P < 0.01) and sperm motility (ï¼»53.50 ± 8.83ï¼½% and ï¼»54.33 ± 7.92ï¼½ %, P < 0.01), and so did those in the high-dose DBC group in pregnancy rate (54.5%, P < 0.01).After medication, the animals showed markedly increased body weight and visceral coefficients of the testis, epididymis and seminal vesicle (P < 0.05 or P < 0.01), recovered morphology of the testis, epididymis and kidneys, reduced levels of Scr, BUN, FSH, LH and MDA in the serum (P < 0.05 or P < 0.01), increased contents of T, SOD and GSH-PX (P < 0.05 or P < 0.01), down-regulated expressions of Bax, Caspase-3 and Caspase-9 and up-regulated expression of Bcl-2 in the renal tissue (P < 0.05 or P < 0.01). CONCLUSIONS: DBC can improve adenine-induced reproductive dysfunction in male rats, which may be attributed to its effects of inhibiting the apoptosis of proteins, improving oxidative stress and elevating the levels of reproductive hormones.

Mechanism of cAMP-PKA Signaling Pathway Mediated by Shaoyao Gancao Decoction () on Regulation of Aquaporin 5 and Muscarinic Receptor 3 Levels in Sjögren's Syndrome.

OBJECTIVE: To investigate the mechanism of cAMP-PKA signaling pathway mediated by Chinese medicine formula Shaoyao Gancao Decoction (, SGD) on the regulation of aquaporin 5 (AQP5) and muscarinic receptor 3 (M3R) levels in Sjögren's syndrome (SS). METHODS: Of the 30 mice, 5 were randomly selected as control, and others were used for creating SS model. After successful modeling, mice were randomly divided into 5 groups (n=5 per group) and intragastrically administered with saline (8 mL/kg), pilocarpine (1.4 mg/kg), or low, medium and high doses SGD (0.14, 0.21, 0.35 g/kg Radix paeoniae with 0.01 g/kg Radix glycyrrhizae, respectively) for 6 weeks. Human labial gland acinar cells were treated with pilocarpine or varying doses of SGD with saline as the placebo. Hematoxylin and eosin staining was used to observe the histopathological changes of the submandibular glands of mice. The serum levels of anti-SS antigen A (SS-A), anti-SS antigen B (SS-B), M3R, and α-fodrin in submandibular glands of mice were measured by enzyme-linked immunosorbent assay. Immunofluorescence staining was used to observe the spatial localization of AQP5 and M3R in acinar cells. Reverse transcriptase polymerase chain reaction and Western blot were used to detect the expressions of PKA, cAMP, Epac1, AQP5, M3R, nuclear factor kappa-B (NF-κB), and tumor necrosis factor (TNF)-α in submandibular gland tissues and cells of each group. RESULTS: Compared to normal mice, body weight, 5-min salivary secretion, 30-min secretion of tears and breakup time of tear film of model mice decreased at 1-6 weeks after immunization (all P<0.05), whereas water intake increased (all P<0.05). In the model group, glands of the submandibular glands showed atrophy, accompanied by acini of different sizes, decreased numbers and loose arrangement, with catheter dilatation and different degrees of lymphocyte infiltration. Conditions of mice in SGD groups were improved. The positive expression of AQP5 and M3R were higher in the acinar cells treated with all doses SGD compared to the normal group; serum levels of SS-A, SS-B, and α-fodrin were lower, and that of M3R was higher in all doses SGD treated animals than the model or pilocarpine treated ones (all P<0.05). Compared to the model and pilocarpine groups, the mRNA and protein levels of NF-κB and TNF-α were lower in mice or cells treated with medium or high-dose SGD (all P<0.05), while those of PKA, Epac1, AQP5 and M3R were higher (all P<0.05). CONCLUSION: SGD can improve symptoms of SS by regulating the cAMP-PKA signaling pathway and increasing AQP5 and M3R levels.

[The characteristics of decomposition and nutrient release of Vicia villosa under different fertilization treatments.] / ä¸åŒæ–½è‚¥æ¡ä»¶ä¸‹æ¯›å¶è‹•å­çš„è è§£åŠå »åˆ†é‡Šæ”¾ç‰¹å¾.

The effects of three fertilization treatments (no fertilizer, nitrogen fertilizer, and lime) on the characteristics of Vicia villosa decomposition and nutrient release were studied using the nylon bag method in the fields. The results showed that the cumulative decomposition rate of V. villosa was 65.3%-72.5% across the three fertilization treatments. V. villosa decomposed rapidly during 0-11 d, then slowed down and tended to be stable. The nutrient release rates across the three treatments were potassium > phosphorus > carbon > nitrogen. At the end of the experiment (148 d), the cumulative release rates of carbon, nitrogen, phosphorus and potassium were 83.6%-84.6%, 78.2%-81.2%, 89.8%-91.4% and 96.3%-97.0%, respectively. During the whole decomposition period, the characteristics of nitrogen release and decomposition of V. villosa were similar. Compared with no fertilizer treatment, lime application promoted decomposition and release of nitrogen, phosphorus and potassium. Nitrogen fertilizer application promoted phosphorus release but inhibited potassium release. Both nitrogen application and lime application had no significant effect on carbon release. The application of nitrogen fertilizer promoted the decomposition of V. villosa and nitrogen release in 0-11 d, but inhibited those processes in 11-148 d. The first-order kinetic reaction equation and logarithmic function equation well fitted the characteristics of V. villosa decomposition and the release of carbon, nitrogen, phosphorus and potassium in the rice fields of South Henan. The characteristic parameters of the equation were significantly correlated with the decomposition rate and nutrient release rate of V. villosa. In summary, lime application was better than nitrogen fertili-zer in promoting decomposition and nutrient release of V. villosa. Moreover, the parameters of the first-order kinetic equation and logarithmic function equation showed a good description of decomposition and nutrient release of V. villosa.

Integrative medicine or infiltrative pseudoscience?

Evidence-based medicine, first described in 1992, offers a clear, systematic, and scientific approach to the practice of medicine. Recently, the non-evidence-based practice of complementary and alternative medicine (CAM) has been increasing in the United States and around the world, particularly at medical institutions known for providing rigorous evidence-based care. The use of CAM may cause harm to patients through interactions with evidence-based medications or if patients choose to forego evidence-based care. CAM may also put financial strain on patients as most CAM expenditures are paid out-of-pocket. Despite these drawbacks, patients continue to use CAM due to media promotion of CAM therapies, dissatisfaction with conventional healthcare, and a desire for more holistic care. Given the increasing demand for CAM, many medical institutions now offer CAM services. Recently, there has been controversy surrounding the leaders of several CAM centres based at a highly respected academic medical institution, as they publicly expressed anti-vaccination views. These controversies demonstrate the non-evidence-based philosophies that run deep within CAM that are contrary to the evidence-based care that academic medical institutions should provide. Although there are financial incentives for institutions to provide CAM, it is important to recognize that this legitimizes CAM and may cause harm to patients. The poor regulation of CAM allows for the continued distribution of products and services that have not been rigorously tested for safety and efficacy. Governments in Australia and England have successfully improved regulation of CAM and can serve as a model to other countries.

Effectiveness of Traditional Chinese Medicine Compound JieDuTongLuoShengJin Granules Treatment in Primary Sjögren's Syndrome: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

OBJECTIVE: To evaluate the clinical therapeutic efficacy and safety of JieDuTongLuoShengJin granules + HCQ in patients with pSS. METHODS: 40 patients with low-activity-level pSS and without visceral involvement participated in this study and were randomized to receive either JieDuTongLuoShengJin granules with HCQ or placebo with HCQ. Patients and investigators were blinded to treatment allocation. The primary endpoint was week 12 ESSPRI score, while secondary endpoints included ESSDAI, salivary and lacrimal gland function, and some laboratory variables. Safety-related data were also assessed. RESULTS: Comparing with the placebo group, the treatment group experienced statistically significant improvement in the mean change from baseline for the primary endpoint of ESSPRI score and also in PGA. Moreover, in comparison with baseline values, the treatment group had significantly improved ESSDAI score, unstimulated saliva flow rate, and several laboratory variables. However, upon comparison of the two groups, there were no significant differences for them. The incidence of AEs was 10.0%, one in treatment group and three in placebo group. CONCLUSION: Treatment with a combination of JieDuTongLuoShengJin granules with HCQ is effective in improving patients' subjective symptoms and some objective indicators of pSS. These results indicate that JieDuTongLuoShengJin is promising as a safe and effective treatment of pSS.

[Relationship Between Seedling Grade of Glycyrrhiza uralensis and Plant Biomass Accumulation, Yield and Quality of Product].

OBJECTIVE: To research the relationship between the seedling grade of Glycyrrhiza uralensis and the biomass accumulation, yield and quality of product, so as to provide basis for establishing seedling standard. METHODS: The weight of single seedling root was measured and the seedlings were divided into three grades by the clustering analysis. The different grade treatments of seedlings were made to conduct field trials and laboratory experiments. RESULTS: The weight of the whole plant and dry root in growth period of grades 1 and 2 (the weight of single root greater than 10.0 g) were larger than grade 3, and the yield was also the case. The root of Glycyrrhiza uralensis, growing for three years, of grades 1 and 2 contained higher contents of active compounds than grade 3 and the content of glycyrrhizin and liquiritin in the root of Glycyrrhiza uralensis of all treatments were higher than the standard of Chinese Pharmacopoeia (2010 edition). CONCLUSION: The plant from the grades 1 and 2 seedlings with larger growth increment,higher output and better quality is the best seedling in cultivation.

[Effect of substrate of edible mushroom on continuously cropping obstacle of Rehmannia glutinosa].

The continuous cultivation of Rehmannia glutinosa causes the accumulation of phenolic acids in soil. It is supposed to be the reason of the so called "continuously cropping obstacle". In this study, phenolic acids (hydroxybenzoic acid, vanillic acid, eugenol, vanillin and ferulic acid) were degraded by the extracta of all the tested spent mushroom substrate (SMS) and the maximal degradation rate was 75.3%, contributed by extraction of SMS of Pleurotus eryngii. Pot experiment indicated that hydroxybenzoic acid and vanillin in soil were also degraded effectively by SMS of P. eryngii. The employment of SMS enhanced ecophysiology index to near the normal levels, such as crown width, leaves number, leaf length, leaf width and height. At the same time, the fresh and dry weight and total catalpol concentration of tuberous root weight of R. glutinosa was increased to 2.70, 3.66, 2.25 times by employment of SMS, respectively. The increase of bacteria, fungi and actinomycetes numbers in rhizosphere soil were observed after the employment of SMS by microbial counts. The employment of SMS also enhanced the enzyme activity in soils, such as sucrase, cellulase, phosphalase, urease and catelase. These results indicated that the employment of SMS alleviated the continuously cropping obstacle of R. glutinosa in some extent.

Combinatorial effects of naomai yihao capsules and vascular endothelial growth factor gene-transfected bone marrow mesenchymal stem cells on angiogenesis in cerebral ischemic tissues in rats.

OBJECTIVE: To investigate the combinatorial effects of Naomai Yihao (NMYH) Capsules and vascular endothelial growth factor (VEGF) gene-transfected bone marrow mesenchymal stem cells (BMSCs) on angiogenesis in cerebral ischemic tissues in rats and the mechanism. METHOD: BMSCs were isolated and cultured from bone marrow by an adherence method. Then, BMSCs were transfected with the eukaryotic expression plasmid pEGFP-VEGF165 by positive ionic liposome transfection. A rat model of middle cerebral artery occlusion (MCAO) was established. Rats were allocated to six groups: model, BMSC, VEGF gene-transfected BMSC transplantation (BMSC/VEGF), NMYH, combined NMYH and BMSC/VEGF (combined treatment group) and sham operation groups. The behavioral rating score (BRS) of rats and the expression of CD34 and VEGF in brain tissue were measured by immunohistochemistry on days 7, 14 and 21 after reperfusion. Angiogenesis was observed and evaluated with laser scanning confocal microscopy. RESULTS: The BRS of rats in NMYH, BMSC transplantation and combined treatment groups was significantly lower than that of the model group (P < 0.001), with no significant difference between NMYH and transplantation groups (P = 0.619). The expression of CD34 and VEGF in NMYH, transplantation and combined treatment groups increased (P < 0.001), with a significant difference between NMYH and transplantation groups (P < 0.001). The blood vessel area in NMYH, transplantation and combined treatment groups was significantly increased (P < 0.05), without a significant difference between NMYH and transplantation groups (P = 0.873). CONCLUSIONS: VEGF gene-transfected BMSCs improve angiogenesis in the cerebral ischemic area. NMYH Capsules promote angiogenesis in MCAO rats treated with BMSC transplantation, which show an improved BRS. The mechanism of angiogenesis may be related to up-regulation of VEGF expression.

Fast transient thermal analysis of gold nanoparticles in tissue-like medium.

Gold-nanoparticle-based hyperthermia has attracted considerable attention in the recent ten years in cancer treatment. In hyperthermia-based cancer treatment, in order to produce efficient thermal therapy yet without excessive heat damage to human body, besides the steady-state thermal condition, the transient thermal response is of vital importance. As part of theoretical research associated with nanoparticle-mediated hyperthermia therapy for cancer treatment, the transient heat transfer process of laser interacting with gold nanoparticle in tissue-like medium is investigated. Within the framework of dual-phase-lag (DPL) model, this paper focuses on the microscopic heat transfer performance of a gold nanoparticle in a surrounding medium. A semianalytical solution of 1-D nonhomogenous DPL equation in spherical coordinates is presented for a heat transfer process with a constant laser heat source and a short-pulsed laser heating source. Results show that the transient temperature calculated by DPL model greatly exceeds that predicted by the classical diffusion model, with either a constant source or a pulsed source. This phenomenon is mainly attributed by the phase lag of heat flux in the surrounding tissue.

Energy absorption of gold nanoshells in hyperthermia therapy.

The unique optical characteristics of a gold nanoshell motivate the application of nanoshell-based hyperthermia in drug delivery and cancer treatment. However, most of our understanding on energy absorption and heat transfer is still focused on individual particles, which may not be accurate for nanoshell aggregates in a real application due to the strong optical interaction of nanoshells. This paper investigates the relationship between the optical interaction and the interparticle distance in the visible and near-infrared regions by means of a finite-difference time-domain (FDTD) method. The objective is to explore the energy transportation mechanism, which is critical for hyperthermia therapy. From the numerical simulation results of different forms of nanoshell aggregates, including individual nanoshells, 1-D chains, 2-D arrays, and 3-D clusters, it was found that the interparticle distance plays a crucial role from the maximal absorption point of view. The interparticle distance affects both field enhancement and surface plasmon resonance position. The accurate prediction of energy absorption also helps the way nanoshells are populated in the tumor cell so as to prevent heat damage to healthy tissues in clinic applications. In the case of 3-D clusters, the laser energy decays exponentially along the wave propagation, and the penetration depth greatly depends on the interparticle distance. The closer the nanoshells are placed, the shorter the penetration depth is. The maximal total length for the laser penetration through the shell of gold nanoparticles is about a few hundred to several nanometers. The actual penetration depth primarily depends not only on the interparticle distance, but also on the size of the nanoshells as well as other factors. Since the absorption energy is concentrated on the surface clusters of nanoparticles, heat transfer mechanisms in metal-nanoparticles-based hyperthermia will differ from that in other hyperthermia. The information obtained from this paper will serve as a basis for further study of heat transfer in metal-nanoparticles-based hyperthermia.