Depot Effect Research Articles

Buprenorphine Salivary Gland Accumulation Sustaining High Oral Fluid Exposure and Increasing the Risk of Streptococcus mutans Biofilm Formation.

The US Food and Drug Administration (FDA) issued a warning about buprenorphine-induced dental caries of unknown mechanism in 2022. To investigate the potential mechanism, the association between local buprenorphine exposure and dental biofilm formation will be explored in this study. Female F344 rats were dosed with sublingual buprenorphine film or intravenous injection to explore the oral cavity exposure of the buprenorphine. The buprenorphine distribution in salivary glands after the sublingual and intravenous administration was also evaluated. To investigate the effects of buprenorphine exposure on dental caries formation, buprenorphine's impact on the biofilm formation of S. mutans in vitro was measured. The absolute sublingual bioavailability of buprenorphine in rats was 17.8% with a high ratio of oral fluid exposure to blood concentration in the pharmacokinetic study. Salivary gland concentrations of buprenorphine and its active metabolite norbuprenorphine were significantly higher than their blood concentrations after both sublingual (s.l.) and intravenous (i.v.) administration. Correlation analysis showed that the oral fluid concentration of buprenorphine and norbuprenorphine was highly correlated to salivary gland concentration rather than blood concentration. These data indicate that the salivary gland serves as an accumulation organ for buprenorphine, allowing prolonged oral fluid exposure to buprenorphine. Lastly, buprenorphine and its metabolites contributed to the biofilm formation of S. mutans in high concentration. Sublingual administration substantially increased the salivary gland distribution of buprenorphine and norbuprenorphine. Depot effects following sublingual dosing and salivary gland accumulation likely sustained high oral fluid exposure to buprenorphine and stimulated the biofilm formation of S. mutans.

7128 Efficacy and Safety of Leuprolide Acetate 3M Depot in Chinese Children with Central Precocious Puberty: Interim Analysis of Multicenter, Single-Arm, Prospective Study

Abstract Disclosure: X. Luo: Advisory Board Member; Self; Takeda. L. Hou: Advisory Board Member; Self; Takeda. Y. Li: Advisory Board Member; Self; Takeda. Y. Sun: Advisory Board Member; Self; Takeda. X.K. Jin: Employee; Self; Takeda. Background: Central precocious puberty (CPP) due to early activation of the hypothalamic-pituitary-gonadal axis leads to early puberty. CPP has a negative impact on adult height. Leuprolide acetate (LA), a gonadotropin-releasing hormone agonist (GnRHa) is the standard treatment for CPP. As CPP requires prolonged treatment, a 3-month (3M) depot formulation would increase patient compliance and reduce the injection burden. This interim analysis presents the effect of LA 3M depot on the gonadotropic axis and assesses safety in children with CPP. Methods: In this open-label, multicenter, single-arm, and prospective study, 31 children with CPP were included. Key inclusion criteria were the appearance of secondary sexual characteristics below the age of eight years in girls and nine years in boys with a confirmed diagnosis of CPP. Children treated with prior GnRHa and/or having underlying medical conditions were excluded. Eligible children were treated with LA 11.25 mg subcutaneously every 12 weeks. The primary endpoint of this interim analysis was the proportion of children achieving inhibition of peak LH defined as peak LH ≤ 3.0 IU/L in the GnRH stimulation test at weeks 24. The secondary endpoint was safety analysis in the children receiving at least one dose of LA 3M depot. Results: At baseline, 30 girls and one boy were enrolled. The median (95% CI) chronological age (CA) of the girls was 8.0 (7.0, 9.0) years and the boy was 10 years old. Girls had a median height of 136.95 (131.5, 139.7) cm, weight of 30 (27, 34) kg, and BMI of 16.4 (15.1, 17.9) kg/m2. Baseline bone (BA) age was 11 (10, 11) years, and BA/CA was 1.24 (1.2, 1.3). Boy’s characteristics at baseline differed in CA (10 years), height (144 cm), and BMI (17.4 kg/m2) from girls of this cohort. Due to the data collection time points for the interim analysis, 8 out of the 31 enrolled subjects had a visit at week 24, and 30 subjects reached the week 12 visit time point and had a visit at week 12. The percentage of children achieving inhibition of peak LH (≤ 3.0 IU/L) in the GnRH stimulation test at week 12 was 100 (88.4, 100) %. At week 24, all of them achieved inhibition of LH in the GnRH stimulation test 100 (63, 100) %. Decreases in BA/CA from baseline at weeks 12 and 24 are 93 (77.9, 99.2) % and 50 (15.7, 84.3) % respectively. No progression of the Tanner stage was observed in 96.7 (82.8, 99.9) % and 100 (63, 100) % at weeks 12 and 24. At the data cut-off, 4 (13.33%) patients experienced a total of 5 treatment-emergent adverse events (TEAEs) in the safety population of 30 subjects. No grade ≥3 AE or serious AE was reported. The incidence of injection site reaction was 3.33%. Conclusion: LA at 11.25mg/3M depot effectively suppresses the gonadotropic axis at weeks 12 and 24, normalizing growth and reversibly slowing the early onset of puberty in children with CPP. LA in a 3-month injecting frequency is a safe and convenient treatment option to improve patient compliance. Presentation: 6/3/2024

Adipose Tissue Oxylipin Profile Changes with Subclinical Ketosis and Depot in Postpartum Dairy Cows

Lipolysis of adipose tissue is a natural occurrence during the periparturient period in dairy cows. However, when lipolysis rates exceed the capacity of other tissues to utilize nonesterified fatty acids (NEFA), it may lead to the development of ketosis and other diseases. Additionally, polyunsaturated NEFA (PUFA) can become oxidized into oxylipins, which modulate inflammation and metabolism. The objective of this work was to identify depot-specific differences on adipose tissue oxylipin profile in dairy cows with and without subclinical ketosis and assess the effects of oxylipins on adipocyte function in vitro. Subcutaneous adipose tissue from the flank (SAT) and visceral adipose tissue from the omentum (VAT) were collected through laparotomy from multiparous dairy cows (5-14 d in milk) and grouped according to blood β-hydroxybutyrate (BHB) into non-ketotic (NK; n = 5; BHB ≤ 0.8 mmol/L) and subclinical ketotic (SCK; n = 5; BHB 1.4 and ≤ 2.6 mmol/L). A targeted lipidome capable of detecting a 154 oxylipins was performed in paired SAT and VAT samples from all animals. Data were analyzed using the PROC GLIMMIX procedure in SAS (v9.4, SAS Institute Inc., Cary, NC, USA) for the effect of depot (SAT, VAT), ketosis status (SCK, NK), and their interaction (depot × ketosis status) on oxylipin abundance. The oxylipins thromboxane-B2 (TXB2), prostaglandin-A2 (PGA2), and 5-hydroxeicostretanoic acid (5-HETE) were selected from lipidomic data based on effects of ketosis status and depot-specificity to further investigate their effects on SAT and VAT adipocyte function. Lipidomic data revealed 50 oxylipins across both adipose tissue depots. SCK was associated with a decreased abundance of TXB2 and tended to associate with an increase in prostaglandinA2 (PGA2) and prostaglandinE1 (PGE1). Additionally, PGE1, 15-keto-prostaglandin-E2 (15-Keto-PGE2), 13,14-dihydro-15-keto-prostaglandin-E2 (13-14dh-15k-PGE2), 5-HETE, and 15-HETE were increased in SAT. While VAT had a greater abundance of 9,10-dihydroxy-12Z-octadecenoic acid (9,10-DiHOME), 12,13-dihydroxy-9Z-octadecenoic acid (12,13-DiHOME), 9-oxo-10E,12Z,15Z-octadecatrienoic acid (9-OxoOTrE) and 13S-hydroxy-9Z,11E,15Z-octadecatrienoic acid (13(s)-HOTrE). In vitro, AVG dose of 5-HETE on VAT cells tended to increase proliferation at d 7 compared with the control, HIGH dose of TXB2 tended to decrease lipid accumulation in SAT compared with control, and AVG dose of PGA2 on VAT cells tended to lower ROS compared with the control. Overall, postpartum dairy cows have depot-specific adipose tissue lipidomic profiles which are associated with changes in ketosis status.

Formulation of Polymeric Nanoparticles Loading Baricitinib as a Topical Approach in Ocular Application.

Topical ocular drug delivery faces several challenges due to the eye's unique anatomy and physiology. Physiological barriers, tear turnover, and blinking hinder the penetration of drugs through the ocular mucosa. In this context, nanoparticles offer several advantages over traditional eye drops. Notably, they can improve drug solubility and bioavailability, allow for controlled and sustained drug release, and can be designed to specifically target ocular tissues, thus minimizing systemic exposure. This study successfully designed and optimized PLGA and PCL nanoparticles for delivering baricitinib (BTB) to the eye using a factorial design, specifically a three-factor at five-levels central rotatable composite 23+ star design. The nanoparticles were small in size so that they would not cause discomfort when applied to the eye. They exhibited low polydispersity, had a negative surface charge, and showed high entrapment efficiency in most of the optimized formulations. The Challenge Test assessed the microbiological safety of the nanoparticle formulations. An ex vivo permeation study through porcine cornea demonstrated that the nanoparticles enhanced the permeability coefficient of the drug more than 15-fold compared to a plain solution, resulting in drug retention in the tissue and providing a depot effect. Finally, the in vitro ocular tolerance studies showed no signs of irritancy, which was further confirmed by HET-CAM testing.

Unlocking Transplant Tolerance with Biomaterials.

For patients suffering from organ failure due to injury or autoimmune disease, allogeneic organ transplantation with chronic immunosuppression is considered the god standard in terms of clinical treatment. However, the true "holy grail" of transplant immunology is operational tolerance, in which the recipient exhibits a sustained lack of alloreactivity toward unencountered antigen presented by the donor graft. This outcome is resultant from critical changes to the phenotype and genotype of the immune repertoire predicated by the activation of specific signaling pathways responsive to soluble and mechanosensitive cues. Biomaterials have emerged as a medium for interfacing with and reprogramming these endogenous pathways toward tolerance in precise, minimally invasive, and spatiotemporally defined manners. By viewing seminal and contemporary breakthroughs in transplant tolerance induction through the lens of biomaterials-mediated immunomodulation strategies-which include intrinsic material immunogenicity, the depot effect, graft coatings, induction and delivery of tolerogenic immune cells, biomimicry of tolerogenic immune cells, and in situ reprogramming-this review emphasizes the stunning diversity of approaches in the field and spotlights exciting future directions for research to come.

Nandrolone treatment of adolescent female rats alters reproductive tissue and gonadal steroid profile

Anabolic androgenic steroids (AAS) are drugs that mimic the chemical structure of testosterone. The most commonly AAS used by young adults is nandrolone. In the USA, more than 20 % of AAS users started using steroids before the age of 20. This is alarming as most female users are unaware of the detrimental reproductive effects of AAS use such as amenorrhea, anovulation and clitoromegaly. An additional detrimental effect of AAS is their addictive liability. Previous studies indicate that animals self-administer AAS. Furthermore, AAS can cross-sensitize with other drugs of abuse such as cocaine. Our goal was to elucidate the effects of both AAS and cocaine in the reproductive system of female rats. Our hypothesis is that AAS will have a detrimental effect on the reproductive system of female rats. Adolescent female rats were divided into two large groups, one that received nandrolone decanoate (20mg/kg/sc) and another that received sesame oil (vehicle) for 10 successive days starting on day 28. Animals were further subdivided into groups that received saline or cocaine injections (0.01cc/10g) for a total of 4 groups: Oil-Saline, ND-Saline, Oil-Cocaine and ND-Cocaine. One cohort (Day 40) received cocaine or saline injections (0.01cc/10g) from days 40 to 44 and on days 52 and day 62. The other cohort (Day 65) received cocaine or saline injections from days 65 to 69 and on days 77 and 87. Our data show that administration of nandrolone during adolescence increased body weight of female rats. Ovarian weight was decreased, and ovarian tissue presented multiple cysts with fewer follicles. Nandrolone also disrupted uterine morphology. The uterine lumen was increased, the endometrial thickness reduced and thickness of myometrial tissue, as well as uterine weight, was increased. In addition, nandrolone reduced both endometrial estrogen and androgen receptors, an effect lost by day 88. In contrast, uterine tissue at day 63 showed an increase in progesterone receptor (PR) immunoreactivity, whereas PR immunoreactivity decreased in tissue obtained at Day 88 regardless of whether animals had received cocaine. Cocaine also increased PR receptors in uterine tissue at day 63 and 88. Animals treated with nandrolone had higher serum concentrations of testosterone and estradiol and a lower level of progesterone. These data show that nandrolone when administered in supraphysiologic doses during adolescence, has long lasting effects on the reproductive system of the female rat due to the depot effects and long half-life of this drug. These data warrant further research in this area to determine the long-term consequences of early nandrolone exposure on the female reproductive system, as well as fertility. Financial assistance was provided by the Offce of International Science and Engineering (OISE) of NSF through the Partnerships for Research and Education (PIRE) Program (OISE-#1545803). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Acute insulin-induced hypoglycemia in twin neonates

Twin neonates with a history of exogenous insulin administration by a mother suffering from post-partum psychosis are reported. Twin 1 presented with lethargy, while twin 2 presented with apnea and bradycardia, requiring vigorous resuscitation. During their neonatal intensive care unit stay, both the babies developed multiple episodes of symptomatic refractory hypoglycemia with seizures and were managed with intravenous dextrose boluses and infusion, glucagon infusion, octreotide, diazoxide, and glucocorticoids. Although short-acting regular insulin (Actrapid, Novo Nordisk™) preparation was administered to the neonates, its effects were seen for a duration of 3–4 days, probably due to the depot effect. We highlight the importance of history taking and physical examination for early diagnosis and appropriate management.

Differential diagnosis in chronic psychosis: a case report

IntroductionA colombian woman aged 62, with previous diagnosis of paranoid schizophrenia. She retired from working 2 years ago, when she started taking care of her sick husband full-time.ObjectivesTo describe a chronic psychosis case and discuss the treatment options and differential diagnosis.MethodsWe used the face-to-face interviews during her last hospitalization and her electronic medical history.We also made a brief research about the effectiveness of risperidone depot in Pubmed.ResultsPsychiatric historyShe’s had 3 hospitalizations, all of them coincided with stressful vital situations. The first one occurred when she was dealing with a job issue. In the second one she was having an economic conflict with her husband. And the third one has coincided with worries about her retirement pension and her caregiver burden.Current episodeShe came to my hospital emergency department distressed because she thought her husband and her were victims of an international drug trafficking plot. She said a colombian drug cartel had sent 9 prostitutes to her village in order to steal from them, by pretending they were cleaning assistants, as a reprisal against her husband, who used to be a military in Colombia . She explained the nature of this event with great details. Also, she said the electric company was involved and they had tried to intoxicate her.The psychopathological exploration was altered with a correct speech in its form but incoherent in its content. She presented a highly structured delusional plot of prosecution. No major affective disorders were detected. She suffered from reactive insomnia and anxiety.EvolutionAt first, it was torpid, she felt perspicacious and angry about the admission. Later, as the antipsychotic started to work, the symptoms improved and she became calm and collaborative. She has never criticized the delusion plot, but it was encapsulated, and the affective resonance disappeared.We tried oral aripiprazole and paliperidone but retired both due to bad tolerance. Then we tried risperidone, with good tolerance and response, and started her current monthly treatment with Risperidone 100 mg depot.After one year, she has kept stable with no relapses and good adherence to the treatment.Differential diagnosisThe patient meets every diagnostic criteria of Delusional disorder (F22), as she has never experienced hallucinations and the functionality has not significantly decreased through the years. Also, she doesn’t meet the second criteria for Schizophrenia (F20).ConclusionsIt is important to explore the evolution of a psychotic disorder in order to differentiate between a schizophrenia and a delusional disorder, as the prognosis differs significantly.Using Risperidone monthly depot can be a good option for treating a psychotic disorder (Sampson et al. Cochrane Database Syst Rev 2016. 14;4(4)).Disclosure of InterestNone Declared

Abstract A141: Preclinical pharmacokinetic (PK) and tumor growth inhibition (TGI) modeling for mANK-101, an anchored murine interleukin-12 (IL-12) complex for intratumoral administration for solid cancer

Abstract Introduction – Murine ANK-101 (mANK-101) is a stable complex composed of a modified murine IL-12 cytokine with aluminum hydroxide at a 1:10 ratio designed for intratumoral delivery to established solid cancers. The objective of this work was to build a preclinical PK/PD/TGI model to gain a better mechanistic understanding of the pharmacology of mANK-101 and potential impact on therapeutic efficacy. Methods - Data were collected from in vivo studies measuring PK, intratumoral immune cells and tumor growth inhibition (TGI) in a CT26 syngeneic mouse model treated with mANK-101. A PK model was derived from Momin et al. [1], the surrogacy potential of immune cells was assessed via a statistical model and subsequently a mathematical model linking immune cell activation to TGI was developed. Results – A two-compartment PK model was established to take into account both the intratumoral depot effect of mANK-101 and the release into the peripheral circulation for mIL12 from the mANK-101 complex. CD8+ T-cell infiltration was found to be a surrogate biomarker for anti-tumor activity and was subsequently used to link PD-TGI. The model was able to capture various doses and schedules of mANK-101 at different starting tumor volumes on therapeutic responses. Conclusions – A PK-PD-TGI model was developed that links the release of mIL12 from mANK-101 to immune cell-activation through to tumor growth inhibition thus providing a causal understanding of the mechanism of action. The model could potentially form the basis of a translational model to assist in designing first-in-man dose and schedule.

Micronanoparticled risedronate exhibits potent vaccine adjuvant effects

Micro/Nano-scale particles are widely used as vaccine adjuvants to enhance immune response and improve antigen stability. While aluminum salt is one of the most common adjuvants approved for human use, its immunostimulatory capacity is suboptimal. In this study, we modified risedronate, an immunostimulant and anti-osteoporotic drug, to create zinc salt particle-based risedronate (Zn-RS), also termed particulate risedronate. Compared to soluble risedronate, micronanoparticled Zn-RS adjuvant demonstrated increased recruitment of innate cells, enhanced antigen uptake locally, and a similar antigen depot effect as aluminum salt. Furthermore, Zn-RS adjuvant directly and quickly stimulated immune cells, accelerated the formulation of germinal centers in lymph nodes, and facilitated the rapid production of antibodies. Importantly, Zn-RS adjuvant exhibited superior performance in both young and aged mice, effectively protecting against respiratory diseases such as SARS-CoV-2 challenge. Consequently, particulate risedronate showed great potential as an immune-enhancing vaccine adjuvant, particularly beneficial for vaccines targeting the susceptible elderly.

Biodistribution of the saponin-based adjuvant Matrix-M™ following intramuscular injection in mice

Novel adjuvants are extensively utilized in the development of safe and effective vaccines against emerging pathogens. Matrix-M™ adjuvant is a saponin-based adjuvant used in several active clinical development programs and in widespread use in the COVID-19 vaccine NVX-CoV2373. Here, we conducted a biodistribution study to better understand the mechanism of action and safety profile for Matrix-M™ adjuvant. Radiolabeled saponins or cholesterol were incorporated into Matrix-A™ particles, which represent 85% of Matrix-M™. Labeled Matrix-M™ adjuvant was given to mice by intramuscular injection with or without SARS-CoV-2 Spike protein. Radioactivity of the adjuvant components was quantified in local and systemic tissues at seven timepoints over a period of 1–168 h. The highest saponin levels were found at the 1-h timepoint at the injection site, in the draining (iliac) lymph nodes, and in urine. Saponins were rapidly cleared from these tissues, reaching very low levels by 48–72 h. Systemically, saponins were found at low levels in the plasma, kidneys, liver, and bone marrow, and were barely detectable in other investigated tissues. Cholesterol was also found at high levels at the injection site and in the draining lymph nodes. These levels declined rapidly at first, then plateaued at 24–48 h. Radiolabeled cholesterol was found at very low levels in other tissues at the earliest timepoints, until increasing and stabilizing after the 24-h timepoint, indicating entry into the endogenous cholesterol recycling pool. This study demonstrates a rapid distribution of Matrix-M™ adjuvant from the injection site to the draining lymph nodes, thus excluding a depot effect as central to the mechanism of action for this adjuvant. The diverging clearance patterns for saponins and cholesterol are suggestive of at least partial disassembly of the Matrix-particles, which has implications for the downstream effects of Matrix-M™ adjuvant on adaptive immune responses. Systemic exposure to toxicologically relevant tissues is very low.

Research Progress of Aluminum Phosphate Adjuvants and Their Action Mechanisms.

Although hundreds of different adjuvants have been tried, aluminum-containing adjuvants are by far the most widely used currently. It is worth mentioning that although aluminum-containing adjuvants have been commonly applied in vaccine production, their acting mechanism remains not completely clear. Thus far, researchers have proposed the following mechanisms: (1) depot effect, (2) phagocytosis, (3) activation of pro-inflammatory signaling pathway NLRP3, (4) host cell DNA release, and other mechanisms of action. Having an overview on recent studies to increase our comprehension on the mechanisms by which aluminum-containing adjuvants adsorb antigens and the effects of adsorption on antigen stability and immune response has become a mainstream research trend. Aluminum-containing adjuvants can enhance immune response through a variety of molecular pathways, but there are still significant challenges in designing effective immune-stimulating vaccine delivery systems with aluminum-containing adjuvants. At present, studies on the acting mechanism of aluminum-containing adjuvants mainly focus on aluminum hydroxide adjuvants. This review will take aluminum phosphate as a representative to discuss the immune stimulation mechanism of aluminum phosphate adjuvants and the differences between aluminum phosphate adjuvants and aluminum hydroxide adjuvants, as well as the research progress on the improvement of aluminum phosphate adjuvants (including the improvement of the adjuvant formula, nano-aluminum phosphate adjuvants and a first-grade composite adjuvant containing aluminum phosphate). Based on such related knowledge, determining optimal formulation to develop effective and safe aluminium-containing adjuvants for different vaccines will become more substantiated.

A "trained immunity" inducer-adjuvanted nanovaccine reverses the growth of established tumors in mice

Innate immune cells are critical in antitumor immune surveillance and the development of antitumor adaptive cellular immunity. Trained innate immune cells demonstrate immune memory-like characteristics, producing more vigorous immune responses to secondary homologous or heterologous stimuli. This study aimed to investigate whether inducing trained immunity is beneficial when using a tumor vaccine to promote antitumor adaptive immune responses. A biphasic delivery system was developed with the trained immunity inducer Muramyl Dipeptide (MDP) and specific tumor antigen human papillomavirus (HPV) E7 peptide encapsulated by poly(lactide-co-glycolide)-acid(PLGA) nanoparticles (NPs), and the NPs along with another trained immunity agonist, β-glucan, were further embedded in a sodium alginate hydrogel. The nanovaccine formulation demonstrated a depot effect for E7 at the injection site and targeted delivery to the lymph nodes and dendritic cells (DCs). The antigen uptake and maturation of DCs were significantly promoted. A trained immunity phenotype, characterized by increased production of IL-1β, IL-6, and TNF-α, was induced in vitro and in vivo in response to secondary homologous or heterologous stimulation. Furthermore, prior innate immune training enhanced the antigen-specific INF-γ-expressing immune cell response elicited by subsequent stimulation with the nanovaccine. Immunization with the nanovaccine completely inhibited the growth of TC-1 tumors and even abolished established tumors in mice. Mechanistically, the inclusion of β-glucan and MDP significantly enhanced the responses of tumor-specific effector adaptive immune cells. The results strongly suggest that the controlled release and targeted delivery of an antigen and trained immunity inducers with an NP/hydrogel biphasic system can elicit robust adaptive immunity, which provides a promising tumor vaccination strategy.Graphical

Dissolvable microneedles for transdermal drug delivery showing skin penetration and modified drug release

Topical therapies for chronic skin diseases suffer from a low patient compliance due to the inconvenient treatment regimens of available products. Dissolvable microneedles (MN) with modified release offer an interesting possibility to increase the compliance by acting as a depot in the skin and thereby decreasing the dosing frequency. Furthermore, the bioavailability can be increased significantly by bypassing the barrier of the skin by the direct penetration of the MN into the skin. In this study the depot effect and skin penetration of an innovative dissolvable MN patch was assessed by insertion in ex vivo human skin and in vivo using minipigs. The MN patches are based on biodegradable polymers and the active pharmaceutical ingredients calcipotriol (Calci) and betamethasone-17–21-dipropionate (BDP) used to treat psoriasis. Using computed tomography (CT) and Coherent anti-Stokes Raman scattering (CARS) microscopy it was possible to visualize the skin penetration and follow the morphology of the MN as function of time in the skin. The depot effect was assessed by studying the modified in vitro release in an aqueous buffer and by comparing the drug release of a single application of a patch both ex vivo and in vivo to daily application of a marketed oleogel containing the same active pharmaceutical ingredients. The CT and CARS images showed efficient penetration of the MN patches into the upper dermis and a slow swelling process of the drug containing tip over a period of 8 days. Furthermore, CARS demonstrated that it can be used as a noninvasive technique with potential applicability in clinical settings. The in vitro release studies show a release of 54% over a time period of 30 days. The pharmacological relevance of MNs was confirmed in human skin explants and in vivo after single application and showed a similar response on calcipotriol and BDP mediated signaling events compared to daily application of the active oleogel. Altogether it was demonstrated that the MN can penetrate the skin and have the potential to provide a depot effect.

GPR120 Gene expression and activity in subcutaneous and intramuscular adipose tissues of Angus crossbred steers.

We hypothesized that media long-chain fatty acids (LCFA) would more greatly depress cyclic adenosine monophosphate (cAMP), glycerol, and free fatty acid (FFA) concentrations in subcutaneous (s.c.) adipose tissue than in intramuscular (i.m.) adipose tissue via G protein-coupled receptor 120 (GPR120). The GPR120 receptor binds to LCFA, which reduces cAMP production, thereby causing a depression in lipolysis. Fresh ex vivo explants of s.c. and i.m. adipose tissue from the fifth to eighth longissimus thoracic rib muscle section of 8, 22-mo-old Angus crossbred steers were transferred immediately to 6-well culture plates containing 3 mL of Krebs-Henseleit buffer/Hepes/5 mM glucose. Samples were preincubated with 0.5 mM theophylline plus 10 μM forskolin for 30 min, after which increasing concentrations of acetate or propionate (volatile fatty acids, VFA) (0, 1, 5, and 10 mM) in the absence or presence of 100 µM oleate (18:1n-9) or 100 μM palmitate (16:0) (LCFA) were added to the incubation media and incubated an additional 30 min. Main effects of adipose tissue depot (i.m. vs. s.c) and VFA (acetate vs. propionate) for adipose tissue concentrations of forskolin-stimulated cAMP were P = 0.747 and P = 0.106, respectively. The addition of LCFA to the media depressed adipose tissue concentrations of cAMP (P = 0.006) (LCFA main effects). The Tissue × VFA × LCFA interaction was not significant for any dependent variable (P ≥ 0.872). Therefore, concentrations of cAMP, glycerol, and FFA were analyzed separately for i.m. and s.c. adipose tissue by split-plot analysis. Concentrations of cAMP, glycerol, or FFA in i.m. and s.c. adipose tissue were not affected by increasing concentrations of VFA (P ≥ 0.497). Media LCFA had no effect on i.m. adipose tissue cAMP (P = 0.570) or glycerol (P = 0.470) but depressed i.m. adipose tissue FFA (P < 0.001). In s.c. adipose tissue, LCFA decreased concentrations of cAMP (P = 0.042) and glycerol (P = 0.038), but increased FFA concentration (P = 0.026). Expression of GPR120 (P = 0.804) and stearoyl-CoA desaturase (P = 0.538) was not different between s.c. adipose tissue and i.m. adipose tissue. The binding of VFA to the GPR43 receptor depresses cAMP production, thereby attenuating lipolysis, but GPR43 mRNA was undetectable in those adipose tissue samples. These results provide evidence for functional GPR120 receptors in s.c. adipose tissue but question the role of GPR43 in the accumulation of adipose tissue lipids in growing steers.

Nanoparticles for Topical Application in the Treatment of Skin Dysfunctions-An Overview of Dermo-Cosmetic and Dermatological Products.

Nanomaterials (NM) arouse interest in various fields of science and industry due to their composition-tunable properties and the ease of modification. They appear currently as components of many consumer products such as sunscreen, dressings, sports clothes, surface-cleaning agents, computer devices, paints, as well as pharmaceutical and cosmetics formulations. The use of NPs in products for topical applications improves the permeation/penetration of the bioactive compounds into deeper layers of the skin, providing a depot effect with sustained drug release and specific cellular and subcellular targeting. Nanocarriers provide advances in dermatology and systemic treatments. Examples are a non-invasive method of vaccination, advanced diagnostic techniques, and transdermal drug delivery. The mechanism of action of NPs, efficiency of skin penetration, and potential threat to human health are still open and not fully explained. This review gives a brief outline of the latest nanotechnology achievements in products used in topical applications to prevent and treat skin diseases. We highlighted aspects such as the penetration of NPs through the skin (influence of physical-chemical properties of NPs, the experimental models for skin penetration, methods applied to improve the penetration of NPs through the skin, and methods applied to investigate the skin penetration by NPs). The review summarizes various therapies using NPs to diagnose and treat skin diseases (melanoma, acne, alopecia, vitiligo, psoriasis) and anti-aging and UV-protectant nano-cosmetics.

Molecular homing and retention of muscle membrane stabilizing copolymers by non-invasive optical imaging in vivo

First-in-class membrane stabilizer Poloxamer 188 (P188) has been shown to confer membrane protection in an extensive range of clinical conditions; however, elements of the systemic distribution and localization of P188 at the organ, tissue, and muscle fiber levels invivo have not yet been elucidated. Here we used non-invasive fluorescence imaging to directly visualize and track the distribution and localization of P188 invivo. The results demonstrated that the Alx647 probe did not alter the fundamental properties of P188 to protect biological membranes. Distribution kinetics in mdx mice demonstrated that Alx647 did not interface with muscle membranes and had fast clearance kinetics. In contrast, the distribution kinetics for P188-Alx647 was significantly slower, indicating a dramatic depot and retention effect of P188. Results further demonstrated the significant retention of P188-Alx647 in the skeletal muscle of mdx mice, showing a significant genotype effect with a higher fluorescence signal in the mdx muscles over BL10 mice. High-resolution optical imaging provided direct evidence of P188 surrounding the sarcolemma of skeletal and cardiac muscle cells. Taken together, these findings provide direct evidence of muscle-disease-dependent molecular homing and retention of synthetic copolymers in striated muscles thereby facilitating advanced studies of copolymer-membrane association in health and disease.

Spatio-temporal delivery of both intra- and extracellular toll-like receptor agonists for enhancing antigen-specific immune responses.

For cancer immunotherapy, triggering toll-like receptors (TLRs) in dendritic cells (DCs) can potentiate antigen-based immune responses. Nevertheless, to generate robust and long-lived immune responses, a well-designed nanovaccine should consider different locations of TLRs on DCs and co-deliver both antigens and TLR agonist combinations to synergistically induce optimal antitumor immunity. Herein, we fabricated lipid-polymer hybrid nanoparticles (LPNPs) to spatio-temporally deliver model antigen ovalbumin (OVA) on the surface of the lipid layer, TLR4 agonist monophosphoryl lipid A (MPLA) within the lipid layer, and TLR7 agonist imiquimod (IMQ) in the polymer core to synergistically activate DCs by both extra- and intra-cellular TLRs for enhancing adaptive immune responses. LPNPs-based nanovaccines exhibited a narrow size distribution at the mean diameter of 133.23nm and zeta potential of -2.36mV, showed a high OVA loading (around 70.83μg/mg) and IMQ encapsulation efficiency (88.04%). Our data revealed that LPNPs-based nanovaccines showed great biocompatibility to immune cells and an excellent ability to enhance antigen internalization, thereby promoting DCs maturation and cytokines production. Compared to Free OVA, OVA-LPNPs promoted antigen uptake, lysosome escape, depot effect and migration to secondary lymphatic organs. Invivo immunization showed that IMQ-MPLA-OVA-LPNPs with dual agonists induced more powerful cellular and humoral immune responses. Moreover, prophylactic vaccination by IMQ-MPLA-OVA-LPNPs effectively suppressed tumor growth and increased survival efficacy. Hence, the nanovaccines we fabricated can effectively co-deliver antigens and different TLR agonists and realize coordinated stimulation of DCs in a spatio-temporal manner for enhanced immune responses, which provides a promising strategy for cancer immunotherapy.

90Y-Labeled Gold Nanoparticle Depot (NPD) Combined with Anti-PD-L1 Antibodies Strongly Inhibits the Growth of 4T1 Tumors in Immunocompetent Mice and Induces an Abscopal Effect on a Distant Non-Irradiated Tumor.

The effectiveness and normal tissue toxicity of a novel nanoparticle depot (NPD) brachytherapy seed incorporating gold nanoparticles (AuNPs) labeled with β-particle emitting, 90Y (termed a "radiation nanomedicine"), were studied for the treatment of 4T1 triple-negative murine mammary carcinoma tumors in Balb/c mice and for inducing an abscopal effect on a distant non-irradiated tumor alone or combined with anti-PD-L1 immune checkpoint antibodies. Balb/c mice with two subcutaneous 4T1 tumors─a primary tumor and a distant secondary tumor were implanted intratumorally (i.t.) in the primary tumor with NPD incorporating 3.5 MBq of 90Y-AuNPs (1 × 1014 AuNPs) or unlabeled AuNPs, alone or combined with systemically administered anti-PD-L1 antibodies (200 μg i.p. three times/week for 2 weeks) or received anti-PD-L1 antibodies alone or no treatment. The primary tumor was strongly growth-inhibited over 14 d by NPD incorporating 90Y-AuNPs but only very modestly inhibited by NPD incorporating unlabeled AuNPs. Anti-PD-L1 antibodies alone were ineffective, and combining anti-PD-L1 antibodies with NPD incorporating 90Y-AuNPs did not further inhibit the growth of the primary tumor. Secondary tumor growth was inhibited by treatment of the primary tumor with NPD incorporating 90Y-AuNPs, and growth inhibition was enhanced by anti-PD-L1 antibodies. Treatment of the primary tumor with NPD incorporating unlabeled AuNPs or anti-PD-L1 antibodies alone had no effect on secondary tumor growth. Biodistribution studies showed high uptake of 90Y in the primary tumor [516-810% implanted dose/g (%ID/g)] but very low uptake in the secondary tumor (0.033-0.16% ID/g) and in normal tissues (<0.5% ID/g) except for kidneys (5-8% ID/g). Very high radiation absorbed doses were estimated for the primary tumor (472 Gy) but very low doses in the secondary tumor (0.13 Gy). There was highdose-heterogeneity in the primary tumor with doses as high as 9964 Gy in close proximity to the NPD, decreasing rapidly with distance from the NPD. Normal organ doses were low (<1 Gy) except for kidneys (4 Gy). No normal tissue toxicity was observed, but white blood cell counts (WBC) decreased in tumor-bearing mice treated with NPD incorporating 90Y-AuNPs. Decreased WBC counts were interpreted as tumor response and not toxicity since these were higher than that in healthy non-tumor-bearing mice, and there was a direct association between WBC counts and 4T1 tumor burden. We conclude that implantation of NPD incorporating 90Y-AuNPs into a primary 4T1 tumor in Balb/c mice strongly inhibited tumor growth and combined with anti-PD-L1 antibodies induced an abscopal effect on a distant secondary tumor. This radiation nanomedicine is promising for the local treatment of triple-negative breast cancer tumors in patients, and these therapeutic effects may extend to non-irradiated lesions, especially when combined with checkpoint immunotherapy.

Lanreotide Depot to Treat Gastroenteropancreatic Neuroendocrine Tumors in a US Community Oncology Setting: A Prospective, Observational Study.

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) can result in symptoms such as diarrhea, flushing, abdominal pain, and fatigue and are often associated with a significant disease burden and poor prognosis. This non-interventional, prospective, observational study evaluated the real-world safety and effectiveness of lanreotide depot, a somatostatin analog (SSA) used to treat GEP-NETs, in a community setting. In this prospective, non-interventional study (NCT02730104), adult patients with locally advanced (inoperable), metastatic GEP-NETs treated with lanreotide depot were evaluated by their physician every 6 months from enrollment for 24months. Clinically defined time to disease progression (TTDP) and overall survival (OS) were estimated for the total population and by primary tumor type (gastrointestinal [GI], pancreatic, unknown origin), and an exploratory analysis determined the rate of progression-free survival (PFS) at 12 and 24months. Patient satisfaction was evaluated via the Treatment Satisfaction Questionnaire for Medication (TSQM-9), and safety information was recorded. Of 99 patients, the 24-month PFS rate was 73.7% (95% confidence interval [CI] 63.1-81.7) and 24-month OS rate was 84.2% (95% CI 74.0-90.7). Median TTDP was not reached because few patients experienced disease progression during the study period. The majority of responding patients expressed satisfaction with treatment on each domain of the TSQM-9. Treatment-related adverse events (AEs) occurred in 19.2% of patients, while no serious AEs (SAEs) were related to the study drug. Lanreotide depot is an effective and well-tolerated treatment for GEP-NETs in the real-world community setting. ClinicalTrials.gov identifier, NCT02730104.