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The architecture and bioactivity of natural products frequently serve as embarkation points for the exploration of biologically relevant chemical space. Total synthesis followed by derivative synthesis has historically enabled a deeper understanding of structure–activity relationships. However, synthetic strategies towards a natural product are not always guided by hypotheses regarding the structural features required for bioactivity. Here, we report an approach to natural product total synthesis that we term ‘pharmacophore-directed retrosynthesis’. A hypothesized, pharmacophore of a natural product is selected as an early synthetic target and this dictates the retrosynthetic analysis. In an ideal application, sequential increases in the structural complexity of this minimal structure enable development of a structure–activity relationship profile throughout the course of the total synthesis effort. This approach enables the identification of simpler congeners retaining bioactivity at a much earlier stage of a synthetic effort, as demonstrated here for the spongiane diterpenoid, gracilin A, leading to simplified derivatives with potent neuroprotective and immunosuppressive activity. Pharmacophore-directed retrosynthesis targets a potential pharmacophore from early on in a natural product synthesis and incremental increases in the complexity of this minimal structure enable a SAR profile to develop over the course of the campaign. The method is applied to gracilin A, finding simplified derivatives displaying potent immunosuppressive effects or selective neuroprotective effects in cell-based assays.

Cyclosporine A (CsA) is an exceptional immunosuppressant used for the treatment of immune disorders. Niosomal vesicles are promising drug carriers that are formed by self-association of nonionic surfactants and cholesterol in an aqueous phase. The objective of the study was to formulate combined nonionic surfactant based vesicles and to evaluate their in vitro characterization, release studies and in vivo studies. Five niosomal formulations (F to F ) were prepared using the thin film hydration method. The molar ratio of cholesterol and non-ionic surfactant taken was 1:1. In formulation F , the combination of surfactants Span 20 and Brij 35 was used. The niosomes were characterized by zeta sizer and SEM for particle size analysis, in vitro drug release and stability studies. The pharmacokinetic studies were conducted on healthy albino rabbits. The size of niosome was found in the range of 427.1 nm to 972.3 nm. SEM image of optimized formulations F exhibit the spherical nature of niosomal vesicles. DSC thermograms of niosomal formulations exhibited a broadened endothermic peak. The stability study exhibited that all formulations are stable and negligible change of vesicle size and entrapment was observed with time. The percentage drug release was significantly higher as compared to CsA plain dispersion for all niosomal formulations at pH 1.2 and 7.4. The release kinetic behavior showed that all preparations were best described by zero order and can release active ingredient in a sustained manner. The pharmacokinetic data showed the test formulation (F10) possessed greater bioavailability as compared to the reference formulation (CsA aqueous dispersion). The formulation F demonstrated a comparatively more delayed rate of release with enhanced dissolution as compared to a single surfactant scheme. The F formulation can be a remarkable nanotechnology for prolonged delivery of CsA orally with improved dissolution profile and bioavailability.

In the past, numerous methods have been developed to predict MHC class II binders or T-helper epitopes for designing the epitope-based vaccines against pathogens. In contrast, limited attempts have been made to develop methods for predicting T-helper epitopes/peptides that can induce a specific type of cytokine. This paper describes a method, developed for predicting interleukin-10 (IL-10) inducing peptides, a cytokine responsible for suppressing the immune system. All models were trained and tested on experimentally validated 394 IL-10 inducing and 848 non-inducing peptides. It was observed that certain types of residues and motifs are more frequent in IL-10 inducing peptides than in non-inducing peptides. Based on this analysis, we developed composition-based models using various machine-learning techniques. Random Forest-based model achieved the maximum Matthews’s Correlation Coefficient (MCC) value of 0.59 with an accuracy of 81.24% developed using dipeptide composition. In order to facilitate the community, we developed a web server “IL-10pred”, standalone packages and a mobile app for designing IL-10 inducing peptides (http://crdd.osdd.net/raghava/IL-10pred/).

Graham Heap, Tariq Ahmad and colleagues show that common variants in the HLA-DQA1–HLA-DRB1 region confer susceptibility to thiopurine-induced pancreatitis in individuals undergoing treatment for inflammatory bowel diseases. These findings could help identify patients at risk of developing this serious adverse reaction to thiopurine therapy. Pancreatitis occurs in approximately 4% of patients treated with the thiopurines azathioprine or mercaptopurine. Its development is unpredictable and almost always leads to drug withdrawal. We identified patients with inflammatory bowel disease (IBD) who had developed pancreatitis within 3 months of starting these drugs from 168 sites around the world. After detailed case adjudication, we performed a genome-wide association study on 172 cases and 2,035 controls with IBD. We identified strong evidence of association within the class II HLA region, with the most significant association identified at rs2647087 (odds ratio 2.59, 95% confidence interval 2.07–3.26, P = 2 × 10 −16 ). We replicated these findings in an independent set of 78 cases and 472 controls with IBD matched for drug exposure. Fine mapping of the HLA region identified association with the HLA-DQA1*02:01–HLA-DRB1*07:01 haplotype. Patients heterozygous at rs2647087 have a 9% risk of developing pancreatitis after administration of a thiopurine, whereas homozygotes have a 17% risk.

Tirabrutinib (Velexbru ® ) is an orally administered, small molecule, Bruton's tyrosine kinase (BTK) inhibitor being developed by Ono Pharmaceutical and its licensee Gilead Sciences for the treatment of autoimmune disorders and haematological malignancies. Tirabrutinib irreversibly and covalently binds to BTK in B cells and inhibits aberrant B cell receptor signalling in B cell-related cancers and autoimmune diseases. In March 2020, oral tirabrutinib was approved in Japan for the treatment of recurrent or refractory primary central nervous system lymphoma. Tirabrutinib is also under regulatory review in Japan for the treatment of Waldenström's macroglobulinemia and lymphoplasmacytic lymphoma. Clinical development is underway in the USA, Europe and Japan for autoimmune disorders, chronic lymphocytic leukaemia, B cell lymphoma, Sjogren's syndrome, pemphigus and rheumatoid arthritis. This article summarizes the milestones in the development of tirabrutinib leading to the first approval of tirabrutinib for the treatment of recurrent or refractory primary central nervous system lymphoma in Japan.

Cyclic peptides are cyclic compounds formed mainly by the amide bonds between either proteinogenic or non-proteinogenic amino acids. This review highlights the occurrence, structures and biological activities of fungal cyclic peptides (excluding cyclodipeptides, and peptides containing ester bonds in the core ring) reported until August 2017. About 293 cyclic peptides belonging to the groups of cyclic tri-, tetra-, penta-, hexa-, hepta-, octa-, nona-, deca-, undeca-, dodeca-, tetradeca-, and octadecapeptides as well as cyclic peptides containing ether bonds in the core ring have been isolated from fungi. They were mainly isolated from the genera Aspergillus, Penicillium, Fusarium, Acremonium and Amanita. Some of them were screened to have antimicrobial, antiviral, cytotoxic, phytotoxic, insecticidal, nematicidal, immunosuppressive and enzyme-inhibitory activities to show their potential applications. Some fungal cyclic peptides such as the echinocandins, pneumocandins and cyclosporin A have been developed as pharmaceuticals.

The increasing prevalence of autoimmune diseases globally has prompted extensive research and the development of immunosuppressants. Currently, immunosuppressive drugs such as cyclosporine, rapamycin, and tacrolimus have been utilized in clinical practice. However, long-term use of these drugs may lead to a series of adverse effects. Therefore, there is an urgent need to explore novel drug candidates for treating autoimmune diseases. This review aims to find potential candidate molecules for natural immunosuppressive compounds derived from plants, animals, and fungi over the past decade. These compounds include terpenoids, alkaloids, phenolic compounds, flavonoids, and others. Among them, compounds 49, 151, 173, 200, 204, and 247 have excellent activity; their IC50 were less than 1 μM. A total of 109 compounds have good immunosuppressive activity, with IC50 ranging from 1 to 10 μM. These active compounds have high medicinal potential. The names, sources, structures, immunosuppressive activity, and the structure-activity relationship were summarized and analyzed.

There has been significant progress in the last few decades in addressing the biomedical applications of polymer hydrogels. Particularly, stimuli responsive hydrogels have been inspected as elegant drug delivery systems capable to deliver at the appropriate site of action within the specific time. The present work describes the synthesis of pH responsive semi-interpenetrating network (semi-IPN) hydrogels of N-succinyl-chitosan (NSC) via Schiff base mechanism using glutaraldehyde as a crosslinking agent and Poly (acrylamide-co-acrylic acid)(Poly (AAm-co-AA)) was embedded within the N-succinyl chitosan network. The physico-chemical interactions were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and field emission scanning electron microscope (FESEM). The synthesized hydrogels constitute porous structure. The swelling ability was analyzed in physiological mediums of pH 7.4 and pH 1.2 at 37°C. Swelling properties of formulations with various amounts of NSC/ Poly (AAm-co-AA) and crosslinking agent at pH 7.4 and pH 1.2 were investigated. Hydrogels showed higher swelling ratios at pH 7.4 while lower at pH 1.2. Swelling kinetics and diffusion parameters were also determined. Drug loading, encapsulation efficiency, and in vitro release of 5-fluorouracil (5-FU) from the synthesized hydrogels were observed. In vitro release profile revealed the significant influence of pH, amount of NSC, Poly (AAm-co-AA), and crosslinking agent on the release of 5-FU. Accordingly, rapid and large release of drug was observed at pH 7.4 than at pH 1.2. The maximum encapsulation efficiency and release of 5-FU from SP2 were found to be 72.45% and 85.99%, respectively. Kinetics of drug release suggested controlled release mechanism of 5-FU is according to trend of non-Fickian. From the above results, it can be concluded that the synthesized hydrogels have capability to adapt their potential exploitation as targeted oral drug delivery carriers.

Th17 responses are critical to a variety of human autoimmune diseases, and therapeutic targeting with monoclonal antibodies against IL-17 and IL-23 has shown considerable promise. Here, we report data to support selective bromodomain blockade of the transcriptional coactivators CBP (CREB binding protein) and p300 as an alternative approach to inhibit human Th17 responses. We show that CBP30 has marked molecular specificity for the bromodomains of CBP and p300, compared with 43 other bromodomains. In unbiased cellular testing on a diverse panel of cultured primary human cells, CBP30 reduced immune cell production of IL-17A and other proinflammatory cytokines. CBP30 also inhibited IL-17A secretion by Th17 cells from healthy donors and patients with ankylosing spondylitis and psoriatic arthritis. Transcriptional profiling of human T cells after CBP30 treatment showed a much more restricted effect on gene expression than that observed with the pan-BET (bromo and extraterminal domain protein family) bromodomain inhibitor JQ1. This selective targeting of the CBP/p300 bromodomain by CBP30 will potentially lead to fewer side effects than with the broadly acting epigenetic inhibitors currently in clinical trials.

Six previously undescribed sesquiterpenoids, aurantiophilanes A–F (1–6), along with six identified analogues (7–12), were isolated from the fungus Aspergillus aurantiobrunneus. Among these, compounds 1 and 3 were identified as highly oxygenated eremophilane sesquiterpenoids, with compound 1 featuring a rare ketone functional group at C-1. The structures of all compounds were unambiguously elucidated using comprehensive spectroscopic analyses, including HRESIMS, NMR, and UV spectroscopy, supplemented by electronic circular dichroism (ECD) analyses and single-crystal X-ray diffraction. All identified compounds were evaluated for immunosuppressive activity; none showed significant effects at concentrations up to 40 µM.