Enhancement and mechanism of transdermal absorption of terpene-induced propranolol hydrochloride

α-Bisabolol: A Dietary Sesquiterpene that Attenuates Apoptotic and Nonapoptotic Cell Death Pathways by Regulating the Mitochondrial Biogenesis and Endoplasmic Reticulum Stress-Hippo Signaling Axis in Doxorubicin-Induced Acute Cardiotoxicity in Rats

The potential for multiorgan toxicities is a significant barrier to the therapeutic use of doxorubicin (DOX) in cancer treatment. With regard to DOX-induced acute cardiotoxicity in rats, the current investigation sought to assess the cardioprotective function of α-bisabolol (BSB) as well as the underlying pharmacological and molecular processes. Acute cardiotoxicity was induced in the rats by the intraperitoneal injection of DOX (12.5 mg/kg, single dosage). Over the course of 5 days, the rats were administered 25 mg/kg of BSB orally twice a day. The DOX administration induced cardiac damage, as evidenced by altered cardiospecific diagnostic markers and macroscopic enzyme mapping assay. The occurrence of mitochondrial oxidative stress was observed by a significant decline in antioxidant defense along with an increase in lipid peroxidation. DOX also perturbed DNA damage, mitochondrial biogenesis, mitochondrial fission and dysfunction, ER stress, Hippo signaling, and caspase-dependent and independent apoptosis including necroptosis and ferroptosis in the myocardium of rats. Conversely, it has been noted that the administration of BSB preserves the myocardium and reverses all cellular, molecular, and structural disruptions in the cardiac tissues of rats exposed to DOX-induced toxicity. The results that are currently available unequivocally show the cardioprotective role of BSB in DOX-induced cardiotoxicity. This effect is attributed to BSB's strong antioxidant, antilipid peroxidative, and antiapoptotic properties, which are mediated by advantageous changes in multiple signaling pathways.

Assessing α-Bisabolol as a Transmucosal Permeation Enhancer of Buccal Local Anesthetics

Needle-free buccal anesthesia improves dental treatment outcomes for both patients and dentists. In this study, we report on an assessment of the enhancement effects of α-bisabolol on the in vitro transmucosal permeation of prilocaine hydrochloride (PCl) and lidocaine hydrochloride (LCl) from needleless buccal films. We also evaluated the mechanical properties of the film, which consisted of Methocel™ K100 LV as the film-forming polymer (3% m·m-1), PEG 400 as a cosolvent (15% m·m-1 based on drug loading), α-bisabolol (15 and 30% m·m-1 based on drug loading), and the drugs combined at a 1:1 ratio (15 mg·unit-1). The porcine esophageal epithelium was used as a membrane barrier, and artificial saliva was the release medium. After a 1 h experiment at 25 ± 2 °C, α-bisabolol significantly decreased, rather than enhanced, the permeation fluxes (five-fold), permeability coefficients (seven-fold), and retentions (two-fold) of both PCl and LCl through the epithelium, regardless of the concentration. Moreover, the resistance and flexibility of the films markedly decreased compared to those without α-bisabolol. Therefore, under the experimental conditions, using α-bisabolol as a buccal permeation enhancer for the hydrophilic local anesthetics PCl and LCl from buccal films is not feasible.

Is Camphor the Future in Supporting Therapy for Skin Infections?

The aim of this review is to present the potential application of camphor-a bicyclic monoterpene ketone-in the prevention of skin infections. Skin diseases represent a heterogeneous group of disorders characterized by prolonged symptoms that significantly diminish the quality of life. They affect the dermis, the epidermis, and even subcutaneous tissue. They very often have a bacterial or fungal background. Therapy for dermatological skin disorders is difficult and long-term. Therefore, it is important to find a compound, preferably of natural origin, that (i) prevents the initiation of this infection and (ii) supports the skin's repair process. Based on its documented anti-inflammatory, antibacterial, antifungal, anti-acne, anesthetic, strengthening, and warming properties, camphor can be used as a preventative measure in dermatological infectious diseases and as a component in medical and cosmetic products. This work discusses the structure and physicochemical properties of camphor, its occurrence, and methods of obtaining it from natural sources as well as through chemical synthesis. The use of camphor in industrial preparations is also presented. Additionally, after a detailed review of the literature, the metabolism of camphor, its interactions with other medicinal substances, and its antimicrobial properties against bacteria and fungi involved in skin diseases are discussed with regard to their resistance.

Effect of invasome composition on membrane fluidity, vesicle stability and skin interactions

Invasomes have been widely exploited to enhance the percutaneous permeation of drugs. On the other hand, few studies have been dedicated to evaluating how their composition impacts the interaction with the skin, vesicle rigidity and stability, which was the focus of this investigation. Light scattering and spectroscopic techniques were considered for vesicle characterization. The addition of cholesterol (CHOL) into the phosphatidylcholine (PC) vesicles led to increased membrane rigidity (from PC:CHOL 5:0.5) and a concentration-dependent disorder effect on skin domains. Nevertheless, these vesicles were showed to be less stable. Ethanol, in turn, resulted in larger and more flexible vesicles, which can be attributed to its preferential distribution in headgroups of PC. The effect of limonene on membrane rigidity was dependent on the vesicle composition. It reduced the rigidity when few constituents were considered, but an opposite effect was observed for vesicles containing PC, CHOL, ethanol and limonene. Competitive effects of limonene and CHOL by the same domains in PC could explain these findings. Limonene was crucial to obtaining more monodisperse vesicles and it showed a synergistic action with CHOL in the disruption of lipid domains in the skin. Invasomes were more stable than liposomes. CHOL-free invasomes showed to be stable for up to 40 days at room temperature.

d-Borneol enhances cisplatin sensitivity via p21/p27-mediated S-phase arrest and cell apoptosis in non-small cell lung cancer cells and a murine xenograft model

Background

Cisplatin (CDDP) is commonly used to treat non-small cell lung cancer (NSCLC), but the appearance of drug resistance greatly hinders its efficacy. Borneol may promote drug absorption; however, synergism between borneol and CDDP in suppressing NSCLC is not clearly understood. Hence, we investigated borneol as a novel chemosensitizer to support chemotherapeutic efficacy and reduce side effects.

Methods

We compared viability after exposure to d-borneol, l-borneol, and synthetic borneol in two NSCLC cell lines, A549 and H460, and selected the most sensitive cells. We then assessed synergy between borneol forms and CDDP in cisplatin-resistant NSCLC cells, H460/CDDP. Next, we identified effective concentrations and exposure times. Subsequently, we evaluated cell migration via wound healing and cell proliferation via clone formation assay. Then, we focused on P-glycoprotein (P-gp) function, cell cycle, apoptosis, and RNA sequencing to elucidate underlying molecular mechanisms for synergy. Finally, we used an H460/CDDP xenograft tumor model to verify antitumor activity and safety in vivo. Data were examined using one-way analysis of variance (ANOVA) for multiple datasets or t-test for comparisons between two variables.

Results

d-Borneol was more effective in H460 than A549 cells. d-Borneol combined with CDDP showed greater inhibition of cell proliferation, migration, and clone formation in H460/CDDP cells than CDDP alone. RNA sequencing (RNA-seq) analysis identified differentially expressed genes enriched in cell cycle pathways. The impact of d-borneol on CDDP chemosensitivity involved arrest of the cell cycle at S phase via p27/p21-mediated cyclinA2/D3-CDK2/6 signaling and activation of intrinsic apoptosis via p21-mediated Bax/Bcl-2/caspase3 signaling. Further, d-borneol ameliorated drug resistance by suppressing levels and activity of P-gp. Cotreatment with d-borneol and CDDP inhibited tumor growth in vivo and reduced CDDP-caused liver and kidney toxicity.

Conclusions

d-Borneol increased the efficacy of cisplatin and reduced its toxicity. This compound has the potential to become a useful chemosensitizer for drug-resistance NSCLC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11658-022-00362-4.

Recent Progress on the Synergistic Antitumor Effect of a Borneol-Modified Nanocarrier Drug Delivery System

Borneol, a traditional Chinese medicine, can enhance therapeutic efficacy by guiding the active ingredients to the target site. Reportedly, borneol improves the penetration capacity of the nasal, cornea, transdermal, intestinal, and blood-brain barriers. Although nanotechnology dramatically changed the face of oncology by targeting tumor sites, the efficiency of nanoparticles delivered to tumor sites is very low, with only 0.7% of the total particles delivered. Thus, based on the penetration ability and the inhibition drug efflux of borneol, it was expected to increase the targeting and detention efficacy of drugs into tumor sites in nanocarriers with borneol modification. Borneol modified nanocarriers used to improve drug-targeting has become a research focus in recent years, but few studies in this area, especially in the antitumor application. Hence, this review summarizes the recent development of nanocarriers with borneol modification. We focus on the updated works of improving therapeutic efficacy, reducing toxicity, inhibiting tumor metastasis, reversing multidrug resistance, and enhancing brain targeting to expand their application and provide a reference for further exploration of targeting drug delivery systems for solid tumor treatment.

Analgesic Potential of Terpenes Derived from Cannabis sativa

Pain prevalence among adults in the United States has increased 25% over the past two decades, resulting in high health-care costs and impacts to patient quality of life. In the last 30 years, our understanding of pain circuits and (intra)cellular mechanisms has grown exponentially, but this understanding has not yet resulted in improved therapies. Options for pain management are limited. Many analgesics have poor efficacy and are accompanied by severe side effects such as addiction, resulting in a devastating opioid abuse and overdose epidemic. These problems have encouraged scientists to identify novel molecular targets and develop alternative pain therapeutics. Increasing preclinical and clinical evidence suggests that cannabis has several beneficial pharmacological activities, including pain relief. Cannabis sativa contains more than 500 chemical compounds, with two principle phytocannabinoids, Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD). Beyond phytocannabinoids, more than 150 terpenes have been identified in different cannabis chemovars. Although the predominant cannabinoids, Δ9-THC and CBD, are thought to be the primary medicinal compounds, terpenes including the monoterpenes β-myrcene, α-pinene, limonene, and linalool, as well as the sesquiterpenes β-caryophyllene and α-humulene may contribute to many pharmacological properties of cannabis, including anti-inflammatory and antinociceptive effects. The aim of this review is to summarize our current knowledge about terpene compounds in cannabis and to analyze the available scientific evidence for a role of cannabis-derived terpenes in modern pain management. SIGNIFICANCE STATEMENT: Decades of research have improved our knowledge of cannabis polypharmacy and contributing phytochemicals, including terpenes. Reform of the legal status for cannabis possession and increased availability (medicinal and recreational) have resulted in cannabis use to combat the increasing prevalence of pain and may help to address the opioid crisis. Better understanding of the pharmacological effects of cannabis and its active components, including terpenes, may assist in identifying new therapeutic approaches and optimizing the use of cannabis and/or terpenes as analgesic agents.

The anti-inflammatory potential of Cinnamomum camphora (L.) J.Presl essential oil in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Borneol was widely used in traditional Chinese medicine formulas due to its pharmacological activities, e.g. sedative, anti-inflammatory, and anti-ischemic properties. Cinnamomum camphora (L.) J.Presl essential oil (BEO) is a by-product of natural crystalline borneol (NCB) production obtained by steam distillation of Cinnamomum camphora (L.) J.Presl leaves, and borneol was the main component of BEO. This study aims to investigate the anti-inflammatory effect of BEO and its corresponding mechanisms through in vitro and in vivo studies.

MATERIALS AND METHODS

Human erythrocyte membrane stability assay and the acute inflammation murine model (xylene-induced ear edema) were chosen to evaluate the anti-inflammatory effect of BEO. Expression of inflammatory mediators, including interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNF-α) was determined by real-time quantitative polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assays (ELISA). The functional compounds in the BEO were identified by using gas chromatography-mass spectrometry (GC-MS). The steady-state transdermal diffusion rates of BEO and BEO nano-emulsion with were also determined in this study. Cytotoxicity of BEO was analyzed by cell counting kit-8 (CCK-8) assay.

RESULTS

The BEO showed a high human erythrocyte membrane stabilization by inhibiting heat-induced hemolysis (IC50 = 5.29 mg/mL) and hypotonic solution-induced hemolysis (IC50 = 0.26 mg/mL) in vitro. The BEO was topically applied to mice auricles, both single and repeated administration significantly reduced xylene-induced auricle swelling (p < 0.0001). Expression of inflammatory mediators, including interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNF-α) in serum and tissue was significantly downregulated (p < 0.05), so as to the mRNA expression of IL-1β (p＜0.05) and TNF-α (p < 0.001). A total of 43 components were identified and quantified by GC-MS. The most abundant was borneol [178.3 mg/mL, 20.9% (m/v)], followed by β-caryophyllene (116.3 mg/mL), camphor (115.2 mg/mL), and limonene (89.4 mg/mL). For determining the skin permeability of BEO, the steady-state transdermal diffusion rates of BEO and BEO nano-emulsion were determined to be 6.7 and 8.9 mg/cm2·h, respectively.

CONCLUSION

It is suspected that the anti-inflammatory effects in vivo and in vitro were derived from the above-mentioned components in the BEO. These findings will facilitate the development of BEO as a new and natural therapeutic agent for inflammatory skin conditions.

Invasome: A Novel Nanocarrier for Transdermal Drug Delivery

Invasomes are novel vesicular systems that exhibit improved transdermal penetration compared to conventional liposomes. These vesicles contain phospholipids, ethanol, and terpene in their structures; these components confer suitable transdermal penetration properties to the soft vesicles. The main advantages of these nanovesicles lie in their ability to increase the permeability of the drug into the skin and decrease absorption into the systemic circulation, thus, limiting the activity of various drugs within the skin layer. In this paper, several features of invasomes, including their structure, mechanism of penetration, applications, characterization, and potential advantages in dermal drug delivery, are highlighted. Overall, this review suggests that enhanced transdermal penetration of drugs using invasomes provides an appropriate opportunity for the development of lipid vesicular carriers.

Transbuccal delivery of benznidazole associated with monoterpenes: permeation studies and mechanistic insights

Benznidazole (BZN) represents the only drug currently available for the treatment of Chagas disease in most endemic countries. When administered orally, high doses are required due to its extensive hepatic metabolism and its toxicity represents the main reason for treatment withdrawals. Because of these complications, transbuccal administration of BZN was investigated. This route avoids the first-pass hepatic metabolism and presents high permeability, with direct access to the systemic circulation. BZN was applied on porcine buccal mucosa after pretreatment with pure eugenol, carvacrol or limonene. Thermal (DSC) and spectroscopic (FT-IR) analyzes were performed to investigate the mechanisms of drug absorption enhancement. The permeability coefficient values of BZN increased 2.6, 2.9 and 4.9-fold after pretreatment with eugenol, carvacrol and limonene, respectively. The lag time, in turn, was shortened in the pretreated samples. The DSC and FT-IR analyzes suggested that transport of BZN through the buccal mucosa is associated with log P and size of monoterpenes. Limonene, the most effective absorption enhancer, contributed to greater interaction with non-polar domains of the buccal epithelium. Overall, BZN showed to be efficiently transported through the buccal route, but in vivo pharmacokinetic studies should be performed to confirm these findings.

Improved Oral Absorption of Poorly Soluble Curcumin via the Concomitant Use of Borneol

In this study, borneol, a natural active compound was applied to improve the bioavailability of curcumin (CUR). In order to increase CUR solubility and dissolution, solid dispersions (SDs) were prepared with the matrix of polyvinylpyrrolidone (PVP) at various ratios by solvent evaporation method. CUR was evidenced to exist as amorphous state in solid dispersion by differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD). Fourier-transform infrared spectroscopy (FT-IR) was utilized to confirm intermolecular hydrogen bonding. The SD at the ratio of 1:3 (CUR:PVP) exhibited the optimal solubility and dissolution rate in various media. The results of ex vivo permeability studies by everted gut sac method showed that the apparent permeability coefficients (P_app) of CUR in SD across the duodenum, jejunum, and ileum had been significantly improved by co-incubation of borneol, and the improvement degree relied on the concentration of borneol. The pharmacokinetic results in rats indicated that the AUC_0-t of CUR-SD (40 mg/kg) co-administration of borneol (90 mg/kg) were 2.53-fold higher than CUR-SD alone, and 19.41-fold higher than pure CUR (200 mg/kg) with borneol (90 mg/kg). Therefore, the combination of borneol and solid dispersion strategy provide a potential approach to enhance the oral bioavailability of CUR.

Aqueous Polymer Dispersion Coating Used for Osmotic Pump Tablets: Membrane Property Investigation and IVIVC Evaluation

The objective of this study was to investigate the fundamental properties of propranolol hydrochloride osmotic pump tablets coated by aqueous polymer dispersion, simultaneously exploring the in vitro and in vivo correlation of the tablet. The physicochemical properties and parameters of aqueous polymer dispersion membranes (SEM, water uptake, and water vapor transmission coefficient) were investigated. In addition, the release behavior and the in vitro release and in vivo absorption profiles of the tablets coated by aqueous polymer dispersion were investigated by comparing with propranolol hydrochloride osmotic pump tablets coated by an organic solvent. Results showed that the similarity factor (f ₂) between cellulose acetate-coated tablet and Eudragit-coated tablet was 78.1, and f ₂ between cellulose acetate-coated tablet and Kollicoat-coated tablet was 77.6. The linear IVIVC of Eudragit-coated and Kollicoat-coated osmotic pump tablets was determined, which confirmed excellent correlation between the absorption in vivo and the drug release in vitro. Consequently, the membrane coated by aqueous polymer dispersion or organic solvent has similar in vitro release rates of controlled release. Also, compared with organic solvent coating, aqueous polymer dispersion has numerous advantages, such as reduced toxicity and no environmental damage. Therefore, the aqueous polymer dispersion technology has enormous potential as a replacement of organic solvent coating.

Influence of Temperature on Transdermal Penetration Enhancing Mechanism of Borneol: A Multi-Scale Study

The influence of temperature on the transdermal permeation enhancing mechanism of borneol (BO) was investigated using a multi-scale method, containing a coarse-grained molecular dynamic (CG-MD) simulation, an in vitro permeation experiment, and a transmission electron microscope (TEM) study. The results showed that BO has the potential to be used as a transdermal penetration enhancer to help osthole (OST) penetrate into the bilayer. With the increasing temperature, the stratum corneum (SC) becomes more flexible, proving to be synergistic with the permeation enhancement of BO, and the lag time (T_Lag) of BO and OST are shortened. However, when the temperature increased too much, with the effect of BO, the structure of SC was destroyed; for example, a water pore was formed and the micelle reversed. Though there were a number of drugs coming into the SC, the normal bilayer structure was absent. In addition, through comparing the simulation, in vitro experiment, and TEM study, we concluded that the computer simulation provided some visually detailed information, and the method plays an important role in related studies of permeation.

Natural Terpenes as Penetration Enhancers for Transdermal Drug Delivery

The greatest hindrance for transdermal drug delivery (TDD) is the barrier property of skin, especially the stratum corneum (SC). Various methodologies have been investigated and developed to enhance the penetration of drugs through the skin. Among them, the most popular approach is the application of penetration enhancers (PEs), including natural terpenes, a very safe and effective class of PEs. In the present paper, we focused on terpenes as skin PEs for TDD. The mechanism of their action, the factors affecting their penetration enhancement effect, as well as their possible skin toxicity were discussed. Terpenes abundant in nature have great potential in the development of PEs. Compared to synthetic PEs, natural terpenes have been proved to possess higher enhancement activity. Interaction with SC intercellular lipids is the main mechanism of action for terpenes. The key factor affecting the enhancement effect is the lipophilicity of both terpenes and drug molecules. In addition, a lot of terpenes have also been proved to be much less toxic compared to azone, the classic synthetic PE. In summary, terpenes may be preferred over the chemically synthesized compounds as safe and effective PEs to promote the percutaneous absorption of drugs.

Transdermal permeation of drugs with differing lipophilicity: Effect of penetration enhancer camphor

The aim of the present study was to investigate the potential application of (+)-camphor as a penetration enhancer for the transdermal delivery of drugs with differing lipophilicity. The skin irritation of camphor was evaluated by in vitro cytotoxicity assays and in vivo transdermal water loss (TEWL) measurements. A series of model drugs with a wide span of lipophilicity (logP value ranging from 3.80 to -0.95), namely indometacin, lidocaine, aspirin, antipyrine, tegafur and 5-fluorouracil, were tested using in vitro transdermal permeation experiments to assess the penetration-enhancing profile of camphor. Meanwhile, the in vivo skin microdialysis was carried out to further investigate the enhancing effect of camphor on the lipophilic and hydrophilic model drugs (i.e. lidocaine and tegafur). SC (stratum corneum)/vehicle partition coefficient and Fourier transform infrared spectroscopy (FTIR) were performed to probe the regulation action of camphor in the skin permeability barrier. It was found that camphor produced a relatively low skin irritation, compared with the frequently-used and standard penetration enhancer laurocapram. In vitro skin permeation studies showed that camphor could significantly facilitate the transdermal absorption of model drugs with differing lipophilicity, and the penetration-enhancing activities were in a parabola curve going downwards with the drug logP values, which displayed the optimal penetration-enhancing efficiency for the weak lipophilic or hydrophilic drugs (an estimated logP value of 0). In vivo skin microdialysis showed that camphor had a similar penetration behavior on transdermal absorption of model drugs. Meanwhile, the partition of lipophilic drugs into SC was increased after treatment with camphor, and camphor also produced a shift of CH2 vibration of SC lipid to higher wavenumbers and decreased the peak area of the CH2 vibration, probably resulting in the alteration of the skin permeability barrier. This suggests that camphor might be a safe and effective penetration enhancer for transdermal drug delivery.

Effect of borneol on the transdermal permeation of drugs with differing lipophilicity and molecular organization of stratum corneum lipids

The aim of the present paper was to investigate the promoting activity of borneol on the transdermal permeation of drugs with differing lipophilicity, and probe its alterations in molecular organization of stratum corneum (SC) lipids. The toxicity of borneol was evaluated in epidermal keratinocyte HaCaT and dermal fibroblast CCC-HSF-1 cell cultures and compared to known enhancers, and its irritant profile was also assessed by transepidermal water loss (TEWL) evaluation. The promoting effect of borneol on the transdermal permeation of five model drugs, namely 5-fluorouracil, antipyrine, aspirin, salicylic acid and ibuprofen, which were selected based on their lipophilicity denoted by logp value, were performed using in vitro skin permeation studies. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) was employed to monitor the borneol-induced alteration in molecular organization of SC lipids. The enhancer borneol displayed lower cytotoxicity or irritation in comparison to the well-established and standard enhancer Azone. Borneol could effectively promote the transdermal permeation of five model drugs, and its enhancement ratios were found to be parabolic curve with the logp values of drugs, which exhibited the optimum permeation activity for relatively hydrophilic drugs (an estimated logp value of -0.5 ∼0.5). The molecular mechanism studies suggested that borneol could perturb the structure of SC lipid alkyl chains, and extract part of SC lipids, resulting in the alteration in the skin permeability barrier.

Metabolic analysis of the increased adventitious rooting mutant of Artemisia annua reveals a role for the plant monoterpene borneol in adventitious root formation

Adventitious root (AR) formation is a critical process for plant clonal propagation. The role of plant secondary metabolites in AR formation is still poorly understood. Chemical and physical mutagenesis in combination with somatic variation were performed on Artemisia annua in order to obtain a mutant with changes in adventitious rooting and composition of plant secondary metabolites. Metabolic and morphological analyses of the iar (increased adventitious rooting) mutant coupled with in vitro assays were used to elucidate the relationship between plant secondary metabolites and AR formation. The only detected differences between the iar mutant and wild-type were rooting capacity and borneol/camphor content. Consistent with this, treatment with borneol in vitro promoted adventitious rooting in wild-type. The enhanced rooting did not continue upon removal of borneol. The iar mutant displayed no significant differences in AR formation upon treatment with camphor. Together, our results suggest that borneol promotes adventitious rooting whereas camphor has no effect on AR formation.

Enhancing effect of borneol and muscone on geniposide transport across the human nasal epithelial cell monolayer

Geniposide is widely used in the treatment of cerebral ischemic stroke and cerebrovascular diseases for its anti-thrombotic and anti-inflammatory effects. Recent studies demonstrated that geniposide could be absorbed promptly and thoroughly by intranasal administration in mice and basically transported into the brain. Here, we explored its transport mechanism and the effect of borneol and muscone on its transport by human nasal epithelial cell (HNEC) monolayer. The cytotoxicity of geniposide, borneol, muscone and their combinations on HNECs was evaluated by the MTT assay. Transcellular transport of geniposide and the influence of borneol and muscone were studied using the HNEC monolayer. Immunostaining and transepithelial electrical resistance were measured to assess the integrity of the monolayer. The membrane fluidity of HNEC was evaluated by fluorescence recovery after photobleaching. Geniposide showed relatively poor absorption in the HNEC monolayer and it was not a P-gp substrate. Geniposide transport in both directions significantly increased when co-administrated with increasing concentrations of borneol and muscone. The enhancing effect of borneol and muscone on geniposide transport across the HNEC may be attributed to the significant enhancement on cell membrane fluidity, disassembly effect on tight junction integrity and the process was reversible. These results indicated that intranasal administration has good potential to treat cerebrovascular diseases.

Systemic delivery of β-blockers via transdermal route for hypertension

Hypertension is the most common cardiovascular disease worldwide. Moreover, management of hypertension requires long-term treatment that may result in poor patient compliance with conventional dosage forms due to greater frequency of drug administration. Although there is availability of a plethora of therapeutically effective antihypertensive molecules, inadequate patient welfare is observed; this arguably presents an opportunity to deliver antihypertensive agents through a different route. Ever since the transdermal drug delivery came into existence, it has offered great advantages including non-invasiveness, prolonged therapeutic effect, reduced side effects, improved bioavailability, better patient compliance and easy termination of drug therapy. Attempts were made to develop the transdermal therapeutic system for various antihypertensive agents, including β-blockers, an important antihypertensive class. β-blockers are potent, highly effective in the management of hypertension and other heart ailments by blocking the effects of normal amounts of adrenaline in the heart and blood vessels. The shortcomings associated with β-blockers such as more frequent dose administration, extensive first pass metabolism and variable bioavailability, make them an ideal candidate for transdermal therapeutic systems. The present article gives a brief view of different β-blockers formulated as transdermal therapeutic system in detail to enhance the bioavailability as well as to improve patient compliance. Constant improvement in this field holds promise for the long-term success in technologically advanced transdermal dosage forms being commercialized sooner rather than later.

Influence of borneol and muscone on geniposide transport through MDCK and MDCK-MDR1 cells as blood-brain barrier in vitro model

The objective of this study was (1) to characterize geniposide transport through MDCK and MDCK-MDR1 cell lines to confirm its transport mechanism and (2) to evaluate the effect of borneol and muscone as enhancers of geniposide transport in the BBB models so as to explore the enhancement mechanism. Transport studies of geniposide were performed in both directions, from apical to basolateral and from basolateral to apical sides. Drug concentrations were analyzed by HPLC. Geniposide showed relatively poor absorption in MDCK and MDCK-MDR1 cells, apparent permeability coefficients ranging from 0.323×10(-6) to 0.422×10(-6) cm/s. The in vitro experiments showed that geniposide transport in both directions was not concentration dependent and saturable, indicating purely passive diffusion. The efflux ratio of geniposide was less than 2 in the two cell models, which suggested that geniposide was not P-gp substrates. Geniposide transport in both directions significantly increased when co-administrated with increasing concentrations of borneol and muscone. Actin staining results indicated that borneol and muscone increased geniposide transport in the BBB models may attribute to disassembly effect on tight junction integrity.

In vitro evaluation of enhancing effect of borneol on transcorneal permeation of compounds with different hydrophilicities and molecular sizes

To investigate the enhancing effect of borneol on transcorneal permeation of compounds with different hydrophilicities and molecular sizes. Six compounds, namely rhodamine B, sodium-fluorescein, fluorescein isothiocyanate (FITC) dextrans of 4, 10, 20 and 40 kDa were selected as model drugs. Permeation studies were performed using excised cornea of rabbits by a Franz-type diffusion apparatus. The safety of borneol was assessed on the basis of corneal hydration level and Draize eye test. The application of 0.2% borneol to the cornea increased the apparent permeability coefficient by 1.82-(P<0.05), 2.49-(P<0.05), 4.18-(P<0.05) and 1.11-fold (not significant) for rhodamine B, sodium-fluorescein, FITC-dextrans of 4 and 10 kDa, respectively. No significant permeability enhancement of FITC dextrans of 10, 20 and 40 kDa with borneol was found compared to control. The permeability coefficient enhanced by 0.2% borneol was linear correlated to the molecular weight of model drugs (R(2)=0.9976). With the 0.05%, 0.1% and 0.2% borneol application, the corneal hydration values were <83% and Draize scores were <4. Borneol may improve the transcorneal penetration of both hydrophilic and lipophilic compounds without causing toxic reactions, especially hydrophilic ones. Furthermore, 0.2% borneol can enhance the permeation of hydrophilic compounds with molecular weight ≤4 kDa. Hence, borneol can be considered as a safe and effective penetration enhancer for ocular drug administration.

Topical herbal medicine combined with pharmacotherapy for psoriasis: a systematic review and meta-analysis

This systematic review examines the current state of the evidence for the efficacy and safety of herbal medicines (HMs) used topically in conjunction with anti-psoriatic pharmacotherapy (APP) in the treatment of psoriasis. Searches were conducted in September 2012 of PubMed, EMBASE, Cochrane Library, two Chinese databases (China National Knowledge Infrastructure and Chinese Scientific Journals Full Text Database) and of article reference lists. We included randomized controlled trials published in English, Chinese or Japanese that investigated topical HM combined with APP used systemically and/or topically compared to pharmacotherapy alone. Studies employing phototherapy were excluded. Two authors conducted searches, extracted data on study characteristics and outcomes, and assessed Risk of Bias. Disagreements were resolved by discussion with a third author. Eight studies met the inclusion criteria. All used multi-herb formulae, four in herbal baths, three in herbal ointments or creams, and one as herbal steam. The pooled data indicated a benefit for the add-on effect of herbal therapy to APP. Adding these topical HMs to conventional pharmacotherapy appeared to produce short-term additional clinical benefits. No serious adverse events were reported. Experimental studies suggest that some of the herbs possess anti-inflammatory, anti-pruritic, and/or anti-proliferative activities. However, these results need to be interpreted with caution due to methodological weaknesses and the lack of replicated studies. Studies that address the identified methodological deficiencies are required to further investigate the efficacy and safety of these HMs as adjunct therapies for psoriasis.