Gating Behavior of Endoplasmic Reticulum Potassium Channels of Rat Hepatocytes in Diabetes

Background: Defects in endoplasmic reticulum homeostasis are common occurrences in different diseases, such as diabetes, in which the function of endoplasmic reticulum is disrupted. It is now well established that ion channels of endoplasmic reticulum membrane have a critical role in endoplasmic reticulum luminal homeostasis. Our previous studies showed the presence of an ATP-sensitive cationic channel in endoplasmic reticulum. Therefore, in this study, we examined and compared the activities of this channel in control and diabetic rats using single-channel recording techniques. Method: Male Wistar rats were made diabetic for 2 weeks with a single dose injection of streptozotocin (45 mg/kg). Ion channel incorporation of rough endoplasmic reticulum of diabetic hepatocytes into the bilayer lipid membrane allowed the characterization of K⁺ channel. Results: Ion channel incorporation of rough endoplasmic reticulum vesicles into the bilayer lipid revealed that the channel current-voltage (I-V) relation with a mean slope conductance of 520 ± 19 pS was unaffected in diabetes. Interestingly, the channel Po-voltage relation was significantly lower in diabetic rats at voltages above +30 mV. Conclusion: We concluded that the endoplasmic reticulum cationic channel is involved in diabetes. Also, this finding could be considered as a goal for further therapeutic plans. Key Words: Endoplasmic reticulum, Diabetes, Ion channels, Bilayer lipid membrane, Liver     

Surface modification of cellulose fibers by layer-by-layer self-assembly of lignosulfonates and TiO2 nanoparticles: Effect on photocatalytic abilities and paper properties

Depositing of TiO₂ nanoparticles on cellulose fiber surface has potential technological applications in the field of photocatalysis. With this motivation, multilayers composed of lignosulfonates (LS) and TiO₂ nanoparticles were constructed on cellulose fiber surface via layer-by-layer (LBL) self-assembly technique. X-ray photoelectron spectroscopy (XPS), zeta potential measurement and atomic force microscopy (AFM) were used to characterize the LS/TiO₂ multilayers on cellulose fiber surface. Moreover, the photocatalytic activities of modified cellulose fibers (decomposition of methyl orange and antibacterial test) were investigated. The decomposition efficiency of methyl orange for a (LS/TiO₂)₅ multilayer modified cellulose fibers was 74.7 % under 5 h UV irradiation. Photocatalytic decomposition efficiency of methyl orange by LS/TiO₂ multilayer modified cellulose fibers under the same UV irradiation time increased linearly with the number of bilayers. Antibacterial tests results revealed that the cellulose fibers modified with LS/TiO₂ multilayers exhibited excellent antibacterial activity against E.coil. The degree of E.coil growth inhibition for a (LS/TiO₂)₅ multilayer modified cellulose fiber reached as high as 93 %. In addition, the effect of LS/TiO₂ multilayers on properties of handsheets made from modified cellulose fibers was also considered. The air permeability of the handsheet prepared from fibers modified with TiO₂/LS multilayers had 6.1–24.3 % higher compared with that of handsheet prepared from original fibers. The wetting properties measurement results demonstrated that the water contact angle of handsheet oscillated with the increasing number of layers depended on building block which was in the outermost layer.     

The Influence of 1-Butanol and Trisodium Citrate Ion on Morphology and Chemical Properties of Chitosan-Based Microcapsules during Rigidification by Alkali Treatment

Linseed oil which has various biomedical applications was encapsulated by chitosan (Chi)-based microcapsules in the development of a suitable carrier. Oil droplets formed in oil-in-water emulsion using sodium dodecyl sulfate (SDS) as emulsifier was stabilized by Chi, and microcapsules with multilayers were formed by alternate additions of SDS and Chi solutions in an emulsion through electrostatic interaction. No chemical cross-linker was used in the study and the multilayer shell membrane was formed by ionic gelation using Chi and SDS. The rigidification of the shell membrane of microcapsules was achieved by alkali treatment in the presence of a small amount of 1-butanol to reduce aggregation. A trisodium citrate solution was used to stabilize the charge of microcapsules by ionic cross-linking. Effects of butanol during alkali treatment and citrate in post alkali treatment were monitored in terms of morphology and the chemical properties of microcapsules. Various characterization techniques revealed that the aggregation was decreased and surface roughness was increased with layer formation.     

Fluorimetric studies of the interactions of wheat puroindolines with polar lipids on the surface starch granules

The interactions of puroindolines with polar lipids were investigated using polarization of fluorescence probes preincorporated into a liposomal bilayer containing PC, PI, PS, MGDG, DGDG, and sulfolipids. The intrinsic fluorescence of Trp residue method was also used. Regardless of the kind of lipid used for liposome preparation, proteins interacted with the liposomes. Conformational changes of the proteins were observed simultaneously with the change in the molecule packing in the lipid bilayer of the liposomes. Puroindoline interactions with the surface of the liposomes have explicit importance for the net charge of this surface. The strong interaction between the proteins and lipids takes place in the presence of a ligand with a negative charge. The obtained results confirm that lipids take part in puroindoline–starch granule surface interactions.     

Thermally induced phase separation in supported bilayers of glycosphingolipid and phospholipid mixtures

The authors have studied microstructure evolution during thermally induced phase separation in a class of binary supported lipid bilayers using a quantitative application of imaging ellipsometry. The bilayers consist of binary mixtures consisting of a higher melting glycosphingolipid, galactosylceramide (GalCer), which resides primarily in the outer leaflet, and a lower melting, unsaturated phospholipid, 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC). Three different bilayer compositions of GalCer/DLPC mixtures at 35:65, 20:80, and 10:90 molar ratios were cooled at controlled rates from their high-temperature homogeneous phase to temperatures corresponding to their phase coexistence regime and imaged in real time using imaging ellipsometry. During the thermotropic course of GalCer gelation, we find that two distinct types of morphological features modulate. First, the formation and growth of chain and fractal-like defects ascribed to the net change in molecular areas during the phase transition. The formation of these defects is consistent with the expected contraction in the molecular area during the liquid crystalline to gel-phase transition. Second, the nucleation and growth of irregularly shaped gel-phase domains, which exhibit either line-tension dominated compact shape or dendritic domains with extended interfaces. Quantifying domain morphology within the fractal framework reveals a close correspondence, and the quantization of the transition width confirms previous estimates of reduced phase transition cooperativity in supported bilayers. A comparison of domain properties indicates that thermal history, bilayer composition, and cooling rate all influence microstructure details including shapes, sizes, and distributions of domains and defects: At lower cooling rates and lower GalCer fractions compact domains form and at higher GalCer fractions (or at higher cooling rates) dendritic domains are evident. This transition of domain morphology from compact shapes to dendritic shapes at higher cooling rates and higher relative fractions of GalCer suggests kinetic control of shape equilibration in these phospho- and glycolipid mixtures.     

Polyelectrolyte multilayer coated nanofibrous mats: Controlled surface morphology and cell culture

We reported the controlled surface morphologies and the cell culture of polyelectrolyte multilayer coated nylon 6 fibrous mats with different number of layers. Polyelectrolyte multilayer coated nylon 6 fibers were successfully prepared by an alternative deposition of alginic acid sodium salt and chitosan via a Layer-by-Layer (LbL) electrostatic self-assembly. The surface morphology, stiffness, and hydrophilicity of polyelectrolyte multilayer coated nylon 6 fibrous mats could be finely tuned by regulating the number of polyelectrolyte nanocoating. It was observed that the morphology of polyelectrolyte multilayer coated nylon 6 fibers was uniform and smooth, indicating a dense and harder nanocoating of polyelectrolytes onto nylon 6 fibers. Compared to pure nylon 6 fibrous mat (tensile strength ～10.6±1 MPa), the tensile strength of polyelectrolyte coated nylon 6 fibrous mats was largely increased to 35.2±2 MPa for 5 bilayers coated fiber mats. In addition, it was found that at an initial stage after 1 day of cell culturing, the electrospun nylon 6 fibrous mats coated with 5 bilayer of alginic acid and chitosan show the highest cell affinity (good adhesion), while the electrospun nylon 6 fibrous mats coated with 10 bilayer show the lowest cell affinity. After cell seeding for 3 days, it was observed that rate of proliferation is enhanced by increasing the number of bilayer up to 3 bilayers (good proliferation), and then drastically decreased with further increasing the number of bilayer.     

Biomimetic assembly of polyelectrolyte multilayers containing phosvitin monitored with reflectometric interference spectroscopy

Coatings of biomaterials or implants that facilitate biomineralization possess a great potential for applications focused to the replacement, augmentation, and regeneration of bone tissue. Biomimetic approaches utilize biomolecules for either templating or supporting the crystallization process. One of these promising biomolecules is phosvitin (PV), an egg yolk protein known to transport and store inorganic phosphates and calcium ions. The incorporation of PV into polyelectrolyte multilayers is favorable due to PVs high degree of phosphorylation and thus a high acidity. Utilizing the reflectometric interference spectroscopy, the adsorption kinetics of this novel polyelectrolyte system composed of poly-L-lysine and the heavily phosphorylated phosvitin were monitored. The results demonstrate an unexpected nonregular growth regime called overshoot. Effective measures of shifting this irregular polyelectrolyte adsorption process back to a regular multilayer growth regime are reported in this paper.     

Structure Elucidation and Functional Studies of a Novel β-hairpin Antimicrobial Peptide from the Marine Polychaeta Capitella teleta

Endogenous antimicrobial peptides (AMPs) are evolutionary ancient molecular factors of innate immunity that play a key role in host defense. Among the most active and stable under physiological conditions AMPs are the peptides of animal origin that adopt a β-hairpin conformation stabilized by disulfide bridges. In this study, a novel BRICHOS-domain related AMP from the marine polychaeta Capitella teleta, named capitellacin, was produced as the recombinant analogue and investigated. The mature capitellacin exhibits high homology with the known β-hairpin AMP family—tachyplesins and polyphemusins from the horseshoe crabs. The β-hairpin structure of the recombinant capitellacin was proved by CD and NMR spectroscopy. In aqueous solution the peptide exists as monomeric right-handed twisted β-hairpin and its structure does not reveal significant amphipathicity. Moreover, the peptide retains this conformation in membrane environment and incorporates into lipid bilayer. Capitellacin exhibits a strong antimicrobial activity in vitro against a wide panel of bacteria including extensively drug-resistant strains. In contrast to other known β-hairpin AMPs, this peptide acts apparently via non-lytic mechanism at concentrations inhibiting bacterial growth. The molecular mechanism of the peptide antimicrobial action does not seem to be related to the inhibition of bacterial translation therefore other molecular targets may be assumed. The reduced cytotoxicity against human cells and high antibacterial cell selectivity as compared to tachyplesin-1 make it an attractive candidate compound for an anti-infective drug design.     

Lipid composition of potatoes during sprouting

The purpose of the study was to determine the lipid composition of potatoes during sprouting. Sprouts from Pontiac and Katahdin potatoes as well as two clones (the genetic material from crosses of a population ofSolanum andigenum from South America andSolanum tuberosum from North America) were found to be significantly higher in crude lipid than either the cortex or pith sections of the tuber. The cortex section was found to be higher in lipid than the pith section. Crude lipid was fractionated into phospholipid, neutral fat, and free fatty acids, and for each of the sections of potatoes the highest percentage of lipid was found in the phospholipid fraction. The fatty acid found in highest concentration in the phospholipid fraction was linoleic acid, but considerable quantities of linolenic and palmitic acids were also present. Synthesis of phospholipid occurs in the actively growing sprout, and compounds that interfere with lipid synthesis, particularly phospholipid synthesis, should prove to be effective sprout inhibitors.     

Combined Effects of Nutrient and Pesticide Management on Soil Microbial Activity in Hybrid Rice Double Annual Cropping System

Combined effects on soil microbial activity of nutrient and pesticide management in hybrid rice double annual cropping system were studied. Results of field experiment demonstrated significant changes in soil microbial biomass phospholipid contents, abundance of heterotrophic bacteria and proteolytic bacteria, electron transport system (ETS)/dehydrogenase activity, soil protein contents under different management practices and at various growth stages. Marked depletions in the soil microbial biomass phospholipid contents were found with the advancement of crop growth stages, while the incorporation of fertilizers and/or pesticides also induced slight changes, and the lowest microbial biomass phospholipid content was found with pesticides application alone. A decline in the bacterial abundance of heterotrophic bacteria and proteolytic bacteria was observed during the continuance of crop growth, while the lowest abundance of heterotrophic bacteria and proteolytic bacteria was found with pesticides application alone, which coincided with the decline of soil microbial biomass. A consistent increase in the electron transport system activity was measured during the different crop growth stages of rice. The use of fertilizers (NPK) alone or combined with pesticides increased it, while a decline was noticed with pesticides application alone as compared with the control. The soil protein content was found to be relatively stable with fertilizers and/or pesticides application at various growth stages in both crops undertaken, but notable changes were detected at different growth stages.     

Nano-TiO<Subscript>2</Subscript> based multilayer film deposition on cotton fabrics for UV-protection

Nano-TiO₂ based multilayer nanocomposite films were fabricated on cationically modified woven cotton fabrics by layer-by-layer molecular self-assembly technique. Cationization process was used to obtain cationic surface charge on cotton fabrics. Attenuated total reflectance Fourier transform infrared spectroscopy analyses were used to verify the presence of cationic surface charge and multilayer films deposited on the fabrics. Scanning electron microscope micrographs of poly(sodium 4-styrene sulfonate)/TiO₂, nano polyurethane/TiO₂, and TiO₂/poly(diallyldimethylammonium chloride) multilayer films deposited on cotton fabrics were taken. With nano-TiO₂ based multilayer film deposition, the protection of cotton fabrics against UV radiation is enhanced. The UV protection durability of the self-assembled multilayer films deposited on the cotton fabrics was analyzed after 10 and 20 washing cycles at 40 °C for 30 min. Air permeability and whiteness value analysis were performed on the untreated and multilayer film deposited cotton fabrics. The effect of layer-by-layer deposition process on tensile strength properties of the warp and weft yarns was determined.     

Structure-Activity Relationships of Holothuroid’s Triterpene Glycosides and Some In Silico Insights Obtained by Molecular Dynamics Study on the Mechanisms of Their Membranolytic Action

The article describes the structure-activity relationships (SAR) for a broad series of sea cucumber glycosides on different tumor cell lines and erythrocytes, and an in silico modulation of the interaction of selected glycosides from the sea cucumber Eupentacta fraudatrix with model erythrocyte membranes using full-atom molecular dynamics (MD) simulations. The in silico approach revealed that the glycosides bound to the membrane surface mainly through hydrophobic interactions and hydrogen bonds. The mode of such interactions depends on the aglycone structure, including the side chain structural peculiarities, and varies to a great extent. Two different mechanisms of glycoside/membrane interactions were discovered. The first one was realized through the pore formation (by cucumariosides A₁ (40) and A₈ (44)), preceded by bonding of the glycosides with membrane sphingomyelin, phospholipids, and cholesterol. Noncovalent intermolecular interactions inside multimolecular membrane complexes and their stoichiometry differed for 40 and 44. The second mechanism was realized by cucumarioside A₂ (59) through the formation of phospholipid and cholesterol clusters in the outer and inner membrane leaflets, correspondingly. Noticeably, the glycoside/phospholipid interactions were more favorable compared to the glycoside/cholesterol interactions, but the glycoside possessed an agglomerating action towards the cholesterol molecules from the inner membrane leaflet. In silico simulations of the interactions of cucumarioside A₇ (45) with model membrane demonstrated only slight interactions with phospholipid polar heads and the absence of glycoside/cholesterol interactions. This fact correlated well with very low experimental hemolytic activity of this substance. The observed peculiarities of membranotropic action are in good agreement with the corresponding experimental data on hemolytic activity of the investigated compounds in vitro.     

Development and evaluation of novel eucalyptus essential oil liposomes/chitosan composite sponges for medical use

Novel eucalyptus essential oil liposomes (EEOLs)/chitosan composite sponges (EC) were successfully fabricated by electrostatic self-assembly. EEOLs were prepared by the thin-membrane hydration method with sonication and blended with chitosan solution to create the sponges by lyophilization. The observations of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) confirmed the existence of eucalyptus essential oil in the lipid bilayer of liposomal membrane and the location of the liposomes in positive holes formed by the protonated amino groups of chitosan. The average size of EEOLs was about 60 nm. Fourier transform infrared (FTIR) analysis showed the destroy of inter- and intramolecular hydrogen bonding among chitosan chains and the construction of the intermolecular hydrogen bonding between chitosan and molecules on the surface of EEOLs. The incorporation of EEOLs in chitosan sponges slightly decreased the porosity, fluid absorptivity, gas permeability and hemostatic property of sponges, but increased their biodegradation ability. EC exhibited more rapid and efficient microbicidal effects against Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa) and Candida albicans (C. albicans) than pure chitosan sponges. EC showed no toxicity toward human HEK293T cells and no significant adverse effect on cell attachment and proliferation of HEK293T cells. This inherent behaviour can be exploited to apply in the medical field.     

橡胶树HbREF3基因的克隆及功能初步分析

橡胶延伸因子（REFs）是橡胶粒子上的一种主要膜蛋白,在橡胶生物合成途径中具有延伸橡胶烃和稳定橡胶粒子等重要作用。对橡胶树不同组织的转录组测序发现,HbREF3在胶乳中具有特异性的高表达,且其在HbREFs基因家族中表达水平也相对较高,仅次于表达丰度最高的HbREF1。HbREF3的开放阅读框为528 bp,编码175个氨基酸,对应的蛋白相对分子质量为19.62 kDa,理论等电点（pI）为5.28。系统进化树分析表明,HbREF3与橡胶树其他HbREFs虽均属于分组Ⅰ,但与HbREF1明显属于不同分支。HbREFs均含有REF保守结构域,但在保守motif的分布上,不同HbREFs蛋白含有保守motif数量不等,HbREF3比HbREF1多了一个motif。生信预测分析表明,该蛋白属于亲水性蛋白,无跨膜结构域,具有14个磷酸化位点。亚细胞定位分析发现HbREF3蛋白定位在内质网上,推测其可能参与橡胶粒子的形成和胶乳的再生。本研究结果为进一步阐明HbREF3基因在橡胶树胶乳再生中的作用机制奠定了基础。     

Quality of potato tubers as affected by freezing: II. lipids and minerals

The effect of freezing on the chemical composition of Katahdin and Atlantic potatoes was studied. Tubers were exposed to a temperature of ?20°C for 24 hrs., then thawed for 1 hr. at 20°C prior to analysis. Frozenthawed tubers were compared with unfrozen controls for total lipid, phospholipid, fatty acid and mineral content. Following freezing, a significant (p<.01) decrease was observed in crude lipid and phospholipid content of both cortex and pith sections. Generally, an increase in palmitic acid and a decrease in linolenic acid occurred in the phospholipid fractions of both varieties. A decrease in both macro and micro mineral content also occurred following freezing.     

Nutritional quality of sunflower seed protein fraction extracted with isopropanol

This study investigated the nutritional effect of sunflower seed proteinfraction (SSPF) extracted with isopropanol on growth, plasma and tissuelipid profile, protein content and erythrocyte membrane lipid profile ofrats. Dehulled sunflower seeds were extracted with isopropanol at 50±1 ^°C resulting in a protein fraction (71.5%) with low residualchlorogenic acid (0.07%) and fiber (3.3%) contents. Rats fed thesunflower seed protein fraction had a similar body weight gain and foodefficiency ratios in comparison to those fed casein. Rats fed SSPF incontrast had a significantly higher growth and food efficiency ratio thanthe rats fed sunflower meal (SM), extracted with hexane. However,dietary proteins exerted a separate effect on plasma total cholesterol,low density lipoprotein (LDL)-cholesterol, low density lipoprotein to highdensity lipoprotein cholesterol (LDL-C/HDL-C) ratio and triglyceridecontent. Sunflower seed protein fraction resulted in a significantdecrease in plasma cholesterol (p < 0.05) and LDL-cholesterol (p <0.02) levels compared to the casein fed rats. Membrane phospholipidprofile also showed a marked variation with the type of dietary protein.Rats fed SSPF and SM did not show much variation in plasma lipids, plasmaproteins, liver and brain lipids and membrane phospholipid concentrations.Protein content, liver and brain lipid profile of the groups fed SSPF andcasein were comparable, suggesting that the nutritional value of SSPF isbetter than SM and equivalent to that of casein.     

Pyranodipyran Derivatives with Tyrosyl DNA Phosphodiesterase 1 Inhibitory Activities and Fluorescent Properties from Aspergillus sp. EGF 15-0-3

Four new benzodipyran racemates, namely (±)-aspergiletals A–D (3–6), representing a rare pyrano[4,3-h]chromene scaffold were isolated together with eurotiumide G (1) and eurotiumide F (2) from the soft-coral-derived fungus Aspergillus sp. EGF 15-0-3. All the corresponding optically pure enantiomers were successfully separated by a chiral HPLC column. The structures and configurations of all the compounds were elucidated based on the combination of NMR and HRESIMS data, chiral separation, single-crystal X-ray diffraction, quantum chemical ¹³C NMR, and electronic circular dichroism calculations. Meanwhile, the structure of eurotiumide G was also revised. The TDP1 inhibitor activities and photophysical properties of the obtained compounds were evaluated. In the TDP1 inhibition assay, as a result of synergy between (+)-6 and (−)-6, (±)-6 displayed strong inhibitory activity to TDP1 with IC₅₀ values of 6.50 ± 0.73 μM. All compounds had a large Stokes shift and could be utilized for elucidating the mode of bioactivities by fluorescence imaging.     

Response of potato tubers to hypoxia followed by re-aeration

Summary Potato tubers kept under hypoxia (1%) showed improved viability in comparison to anoxia, which was associated with the maintenance of intermediate adenylate energy charge values (A.E.C.=0.6) and stable adenylate pools at 50% of the initial levels. Re-admission of oxygen to the tuber resulted in an almost full recovery of adenylate energy charge and total adenylates after up to 3 days of hypoxic pretreatment. Tubers exhibited a mixed fermentation. The high lactate, ethanol and acetaldehyde levels proved to be non toxic. Ethanol was degraded to acetaldehyde during re-aeration. Posthypoxic lipid peroxidation was indicated by malondialdehyde and ethane formation. Both products occurred with a temporary delay and in lower amounts compared to post-anoxia. Ethylene release was also considerably smaller. Severe hypoxia and posthypoxia postponed tissue death compared to anoxia. Survival was correlated with an improved energy supply which stabilized membranes.     

Thiamin (vitamin B1) and thiamin phosphate esters in five cereal grains during maturation

Non-phosphorylated thiamin (T), thiamin monophosphate (TMP), and thiamin diphosphate (TDP) were extracted from whole grains of wheat (Triticum aestivum, cv. Dekan), triticale (Triticosecale, cv. SW Talentro), rye (Secale cereale, cv. Agronom), oats (Avena sativa, cv. Dominik), and barley (Hordeum vulgare, cv. Merlot) at different growth stages (from inflorescence emergence to full ripeness of the grains) and determined with high-performance liquid chromatography and fluorescence detection. No thiamin triphosphate or adenosine thiamin triphosphate was found in these cereals. Total thiamin levels (the sum of T and its phosphate esters) determined on a dry matter (DM) basis were found to be quite similar in all grain samples throughout the analysis period, ranging from 5.59 (wheat) to 13.00 nmol/g DM (oats). In spikelets 3–5 days after flowering, the total thiamin content in all cereals was 40–75% T, 5–13% TMP, and 18–46% TDP. Generally, T increased and TDP decreased continuously with grain development, with maximum T (88–99%), and minimum TDP (2–10%) at ripeness. No TMP was detected in mature grains. The results indicate that variation in T, TMP, and TDP levels is probably due above all to the conversion of phosphorylated thiamin phosphate esters into less highly or non-phosphorylated forms.     

Optimizing interfacial features to regulate neural progenitor cells using polyelectrolyte multilayers and brain derived neurotrophic factor

The development of biomaterials with controllable interfacial features which have the capability to instruct cellular behavior are required to produce functional scaffolds for the treatment of spinal cord injury (SCI). Here, poly-?-caprolactone surfaces were biofunctionalized via layer-by-layer (LbL) deposition. The polyelectrolytes employed in this LbL technique were heparin and poly-L-lysine (PLL), the latter being chosen to improve cell adhesion and the subsequent cellular function of in vitrocultured neural progenitor cells. Material characterization results confirmed the deposition of well structured multilayers. Cell culture studies revealed significant differences in the cellular response to these adhesive/nonadhesive (PLL/heparin) polyelectrolyte multilayer (PEM)surfaces, with neurite outgrowth being significantly promoted on the PLL terminating layers. In addition, brain derived neurotrophic factor (BDNF) was adsorbed onto the LbL surfaces. This combined chemical and biological effect was then characterized in terms of neurite length along with the full length/truncated isoform 1 tyrosine kinase receptor (TrkB-FL/TrkB-T1) and growth associated protein-43 mRNA levels. Here, the authors report the differential effect of adsorbed and soluble BDNF of different concentrations. Adsorbed BDNF promoted neurite outgrowth and led to elevated, sustained TrkB mRNA levels. These findings highlight the potential of PEM biofunctionalized surfaces with integrated chemical and neurotrophin supportive cues to overcome SCI inhibitory environments and to promote regeneration.