Molecular Pharmaceutics最新文献

The inflammation response is a prominent sign of myocardial infarction (MI), mediating the process of cardiac fibrosis and ventricular remodeling. Inflammation visualization holds new promise for guiding cardiac anti-inflammatory therapy. Interleukin-4 receptor α (IL4Rα) interacts with IL4, closely related to macrophage polarization. This study aimed to evaluate the feasibility of a technetium-99m (^99mTc) labeled IL4Rα antibody probe ([^99mTc]Tc-HYNIC-CM310) for targeting postinfarction macrophage SPECT imaging. [^99mTc]Tc-HYNIC-CM310 was prepared by radiolabeling an IL4Rα-specific monoclonal antibody (CM310) with ^99mTc. Images were acquired at 0.5, 6, 12, 24, and 36 h postinjection on the next day after MI and the sham model preparation, and a biodistribution study was performed at 36 h. The mean percentage of injected dose per gram (%ID/g) of various tissues was obtained by drawing the regions of interest. [¹⁸F]FDG myocardial metabolism and inflammation imaging were performed for comparison and verification. Immunofluorescence costaining and flow cytometry were conducted to validate the coexpression of IL4Rα and macrophages. The radiolabeling yield of [^99mTc]Tc-HYNIC-CM310 was approximately 88.31% ± 1.70%, and the radiochemical purity was 93.70% ± 0.38%. The accumulation of [^99mTc]Tc-HYNIC-CM310 in infarcted myocardium was increased starting at 12 h postinjection. The tracer uptake was significantly higher in the infarcted myocardium than the same site in sham-operated rats (P < 0.05). The tracer uptake region was consistent with the cardiac metabolic defect and inflammatory region seen by [¹⁸F]FDG PET. Immunofluorescence staining and flow cytometry confirmed the colocalization of IL4Rα⁺ cells and macrophage markers in the infarcted myocardium. We successfully prepared and validated the SPECT probe [^99mTc]Tc-HYNIC-CM310 for precise visualization of macrophages, offering a new opportunity for guiding the treatment of cardiac inflammation.

The poor water solubility of active pharmaceutical ingredients (APIs) poses a significant challenge in pharmaceutical development, affecting their bioavailability and therapeutic efficacy. Consequently, there is an urgent demand for strategies to improve API solubility, with hydrotropy emerging as one of the most effective approaches. Hydrotropes, which can act as excipients in pharmaceutical formulations, enhance solubility by solubilizing hydrophobic compounds in aqueous solutions through mechanisms other than micellar solubilization. However, identifying the right hydrotropic agent requires a screening from a large pool of candidates. This work aims to analyze hydrotropy from a thermodynamic perspective by investigating the influence of the molecular interactions among the API, hydrotrope, and water on the API solubility in water at different temperatures. For this systematic study, hypothetical ternary systems were used and only liquid hydrotropes were considered. Utilizing the Two-Suffix Margules equation to model the liquid phase nonideality, the study revealed that strong API-hydrotrope interactions notably enhance the API solubility in water. Additionally, the interaction between the hydrotrope and water significantly influences API solubility; weaker hydrotrope-water interactions allow for increased API solubility in water. However, when hydrotrope-water interactions are stronger than API-hydrotrope interactions, this effect is diminished. The theoretical findings were validated using solubility experimental data of syringic acid with alkanediols in water from the literature. The results of this work will aid in selecting suitable liquid hydrotropes for enhancing the API solubility in aqueous solutions.

Water plays a critical role in chemical degradations, such as deamidation, in freeze-dried proteins. Two distinct patterns for deamidation in relation to water have been reported, that is a "hockey stick"-type behavior with a water-independent deamidation rate, followed by a sharp increase above a water content threshold, and an inverted bell-shaped profile. To understand the underlying mechanism, molecular dynamics simulations are employed to study the explicit water distributions around reactive sites for amorphous and crystalline insulin as well as amorphous IgG1. The simulated water distribution on the protein surface is first validated by successfully predicting water vapor sorption isotherms for both amorphous and crystalline insulin. The "hockey stick"-type behavior is explained by a water threshold level beyond which there are two (Asn-Gly sequence in IgG1) or three (Asn at the C-terminus in insulin) water molecules assisting the cyclization reactions. Regarding the inverted bell-shaped profile for amorphous IgG1, the initial decreases in deamidation rate with increasing water content at low water levels can be rationalized by a lower density and higher free volume of IgG1 at a lower water content. When the free volume exceeds a percolation threshold, the produced ammonia gas can easily diffuse away, lowering the back reaction rate and thus raising the overall reaction rate. The "free volume" mechanism can also be applied to the abnormal stability ranking orders of crystalline and amorphous insulin. The faster deamidation and dimerization rates in insulin crystals compared to amorphous insulin as reported by Pikal and Rigsbee are due to the lower density and higher free volume (above the percolation threshold) in crystalline insulin, assuming that dehydration of insulin crystals does not result in a major collapse of the crystal structure.

Mannitol is widely employed as a bulking agent in lyophilized formulations. Our goal was to evaluate the role of noncrystallizing cosolutes in inhibiting mannitol crystallization and preventing the formation of mannitol hemihydrate (MHH) in frozen solutions. The individual influence of two common stabilizers (sucrose and trehalose) and three model proteins (lysozyme, bovine serum albumin, and immunoglobulin G) on the crystallization behavior of mannitol was investigated by differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). Sugars exerted a more pronounced crystallization inhibitory effect than proteins. In the presence of sugars, mannitol predominantly crystallized as MHH while the proteins facilitated the crystallization of δ-mannitol. Annealing the frozen solutions at -25 °C favored MHH crystallization. A higher annealing temperature of -10 °C accelerated mannitol crystallization and promoted the formation of the anhydrous δ-polymorph. The crystallization inhibitory effect of proteins was surmounted with annealing, while at a high sugar concentration, a substantial fraction of mannitol was retained amorphous even after annealing.

Nitroaromatic compounds (NACs) are generally used as starting materials and/or generated as byproducts during the manufacturing of dyes, fertilizers, and therapeutic agents. Though NACs are beneficial when used appropriately, inadequate management, disposal, and application methods have led to their introduction to bacterial ecosystems where NACs act as mutagenic agents and may even contribute to antimicrobial resistance. Many of these bacterial systems are known to have different pathways to adapt to the presence of NACs such as altering the lipid composition of cellular membranes and intracellular degradation of NACs. In general, these processes require sophisticated techniques and skilled human resources to detect the changes by conventional characterization techniques. Hence, alternative methods are needed to investigate the short-term effects of NACs on bacterial cells with better precision. Herein, we report that bacterial cells adapt to the presence of NACs initially by incorporation in the cellular membrane, which can be predicted by further altered electrical and electrochemical properties of the cells. It was observed that the whole cell bacteria were negatively charged entities that could generate varying levels of surface charges on being incubated with model NACs of biomedical importance viz. niclosamide and p-nitrophenol. Such variations were also reflected in dye entrapment assays performed by using lipidic membranes collected from NAC-treated bacterial cells after the cells. Further studies with gel electrophoresis and differential pulse voltammetry revealed the significant alterations in electrochemical properties of NAC-incubated bacterial cells. Overall, results indicate that bacterial adaptation to NACs was found to be closely linked to variations in the electrochemical properties of the bacterial cells. These outcomes advance our understanding of influences imparted by NACs during bacterial infections and might facilitate the way for developing therapies to combat antibacterial resistance in the near future.

Peritoneal fibrosis (PF) is a common complication in peritoneal dialysis patients with end-stage renal disease. This study established a rat model of PF, used ⁶⁸Ga-FAPI PET/CT imaging to visualize PF, and evaluated the therapeutic effects and mechanism of action of sodium butyrate. The rat model of PF (n = 20) was induced by hyperglycemic peritoneal dialysate combined with lipopolysaccharide, the control group (n = 20) was given the same amount of normal saline, and the intervention group (n = 20) was given sodium butyrate by intraperitoneal injection. At 2, 4, 6, and 8 weeks, a peritoneal equilibration test was performed, and peritoneal tissues were collected for histological staining. Three rats from each group were randomly selected for ⁶⁸Ga-FAPI small animal PET/CT imaging. Compared with control rats, model group rats presented a decreased ultrafiltration volume, increased maximum glucose transport (P < 0.05), increased peritoneal thickness and fibrosis area, and upregulated α-SMA, COL I, TGF-β1, Smad3, and p-Smad3 expression in peritoneal tissues (P < 0.05) in a time-dependent manner. The sodium butyrate group improved peritoneal transport function (P < 0.05), alleviated collagen deposition, and downregulated α-SMA, COL I, TGF-β1, Smad3, and p-Smad3 while increasing Smad7 expression in peritoneal tissues (P < 0.05). ⁶⁸Ga uptake was markedly increased in the model group (P < 0.05) but was reduced after sodium butyrate treatment (P < 0.05). The SUVmax was positively correlated with peritoneal thickness; maximum glucose transport; and α-SMA, COL I, and FAP-α expression (r = 0.871, 0.845, 0.843, 0.659, 0.926) but negatively correlated with ultrafiltration volume (r= -0.894). In summary, ⁶⁸Ga-FAPI PET/CT could be a promising noninvasive approach for assessing peritoneal fibrosis that is superior to and safer than peritoneal biopsy. Sodium butyrate may attenuate peritoneal fibrosis by regulating the TGF-β1/Smad3 signaling pathway.

Enhanced transport of immunomodulators via the lymphatics may increase drug exposure to therapeutic targets in the immune system. Our laboratory has demonstrated a triglyceride (TG) mimetic prodrug approach to enhance the lymphatic delivery of a model immunomodulator, mycophenolic acid (MPA), via conjugation of the carboxylic acid of MPA to a TG backbone, where the so formed prodrug is able to incorporate into intestinal TG deacylation-reacylation and lymph lipoprotein transport pathways (up to 37% of the administered dose being absorbed via the lymphatics). In the current study, another conjugation site in the molecule of MPA, i.e., the phenolic group, was explored for its potential to optimize the lymphatic transport profiles of TG mimetic prodrugs of MPA. This offers an unusual opportunity to directly compare the utility of TG prodrugs formed via conjugation to an acid versus a phenol in the same core molecule, which has not been examined previously for other parent drugs. A series of linkers were examined to connect the MPA moiety with the TG backbone. Lymphatic transport was assessed in mesenteric lymph duct cannulated rats, and drug exposure in the mesenteric lymph nodes was examined following oral administration to mice. Compared to the data observed previously for MPA prodrugs conjugated via the carboxylic acid, the new phenol-conjugated prodrugs showed clearly different profiles in terms of the linker chemistry. Prodrugs with shorter chain alkyl spacers (e.g., C4 and C6) supported minimal lymphatic transport (<3% of the dose recovered in lymph). When the chain lengths were longer (≥C10), the prodrugs demonstrated much higher potential for lymphatic transport (up to approximately 55% of dose). Although effectively promoting lymphatic transport, TG mimetic prodrugs with alkyl chain linkers did not necessarily result in marked increases in the exposure of MPA in the mesenteric lymph nodes in mice. Subsequently a number of self-immolative linkers conjugated via the phenol were explored to promote MPA liberation from the prodrugs, and these constructs demonstrated enhanced lymph node exposure. This study provides further insight into structure-lymphatic transport relationships for lymph-directing lipid mimetic prodrugs.

Alcohol liver disease (ALD) is a chronic liver disorder resulting from long-term heavy alcohol consumption. The pathogenesis of ALD is multifactorial, and existing therapeutic agents primarily target specific aspects of the disease while presenting significant side effects, including drug-induced liver injury and hepatobiliary disease. Silibinin (SLB) has attracted widespread attention for its hepatoprotective effects and favorable safety profile. However, inherent limitations associated with SLB, such as poor solubility and bioavailability, have significantly limited its clinical application. Drug delivery systems, including liposomes, offer promising potential for the delivery of hydrophobic drugs. However, the selection of an appropriate delivery vehicle requires optimization. Ursodeoxycholic acid sodium (UAS) serves as a promising alternative to cholesterol in liposomal formulations, offering a potential strategy to mitigate the health risks associated with cholesterol. In this study, UAS was employed as the liposomal membrane material to prepare a UAS liposome loaded with SLB (SUL), and its efficacy and mechanism of action in alcoholic-induced liver injury were subsequently evaluated. The experimental results demonstrated that SUL exhibited a uniform particle size distribution, good stability, and an effective release profile in vitro. Following oral administration, SUL effectively inhibited alcohol-induced liver damage, oxidative stress, and fat accumulation. In addition, SUL regulated the expression of the kelch-1ike ECH- associated protein l (Keap1), nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase 1 (HO-1) proteins, thereby exerting antioxidative stress effects. Furthermore, it also modulated apoptosis-related factors, including B-cell lymphoma-2 (Bcl-2), BCL-2-associated X (Bax), cysteinyl aspartate specific proteinase-3 (Caspase-3), and cleaved caspase-3, to mitigate hepatocyte apoptosis. In summary, SUL demonstrates enhanced therapeutic efficacy against ALD, offering a novel approach for the clinical application of SLB in the prevention and treatment of ALD.

Monoclonal antibodies (mAbs) are changing cancer treatments. However, the presence of the blood-brain barrier (BBB) and the blood-tumor barrier (BTB) limits the use of mAbs to treat brain cancer or brain metastasis. Molecules that hijack endogenous transport mechanisms on the brain endothelium (brain shuttles) have been shown to increase the transport of large molecules and nanoparticles across the BBB. Among these shuttles, protease-resistant peptides such as MiniAp-4 are particularly efficient. Here, we report the synthesis, characterization, and evaluation of site-specific mAb-brainshuttle antibody conjugates (ASC) based on the anti-HER2 mAb trastuzumab (Tz) and four molecules of MiniAp-4. The ASCs preserve the binding and cell cycle arrest capacity of Tz. MiniAp-4 ASC displays enhanced transport across an in vitro BBB cellular model with respect to Tz and Tz conjugated to Angiopep-2, the brain shuttle that has advanced the most in clinical trials. More importantly, evaluation of Tz-MiniAp4 in a murine brain metastasis model demonstrated that the protease-resistant peptide showed preferential transport across the BBB/BTB, displaying a marked therapeutic effect and protecting against metastasis development. The technology described herein could be applied to any antibody of interest to treat central nervous system-related diseases. MiniAp-4 enhances the brain transport of the monoclonal antibody trastuzumab, preventing brain metastasis.