Discovery of water-soluble semicarbazide-containing sulfonamide derivatives possessing favorable anti-glaucoma effect in vivo and drug-like properties.

In order to obtain topical and non-irritating anti-glaucoma drugs, novel semicarbazide-containing sulfonamide derivatives were designed and synthetized by sugar tail method in this study. The hydrophilic monosaccharides were expected to form interaction with the hydrophilic site of hCA II meanwhile the linker semicarbazides are used to further enhance water solubility, and more importantly, regulate the pH values of the target compounds in aqueous solution. First, all target compounds were synthesized and evaluated for their CA inhibitory activities. The results showed our target compounds demonstrated comparable activity to the positive control drug acetazolamide. The best derivative 11d exhibits an IC50 value of 14 nM for hCA II and 2086-fold selectivity over CA I. Subsequently, physicochemical properties study showed that the target compounds displayed very good water solubility (up to 3 %) and neutral pH value in solutions. Meanwhile, the artificial membrane permeability assay was performed to verify that the target compound could also pass through the membrane structure despite their strong water solubility. In the glaucomatous rabbit eye model, the applied topically representative compounds showed strongly lowered intraocular pressure (IOP), as 1 % or 2 % water solutions. Subsequent drug-like evaluation showed our target compounds possessed low hemolysis effect and low cytotoxicity toward human corneal epithelial cell line. Also, it was not found that these target compounds had significant inhibition of hERG and CYP. In addition, these novel analogs also displayed good liver microsomal metabolic stability and plasma stability. Finally, docking studies provided the rational binding modes of representative compounds in complex with hCA II. Taken together, these results suggested that compound 11d may be a promising hCA II inhibitor deserving further development.

Design, Synthesis and Biological Evaluation of New Carbohydrate-Based Coumarin Derivatives as Selective Carbonic Anhydrase IX Inhibitors via "Click" Reaction.

In this work, we designed a series of new carbohydrate-based coumarin carbonic anhydrase IX inhibitors by using 1,2,3-triazoles as linker. Next, these designed compounds were synthesized by the optimized one-pot click chemistry reaction condition. Subsequently, these target compounds were assayed for the inhibition of three carbonic anhydrase isoforms (CA I, CA II and CA IX). Intriguingly, all the compounds showed better CA IX inhibitory activity than initial coumarin fragments. Among them, compound 10a (IC50: 11 nM) possessed the most potent CA IX inhibitory activity, which was more potent than the reference drug acetazolamide (IC50: 30 nM). Notably, compound 10a showed 3018-fold, 1955-fold selectivity relative to CA I and CA II, respectively. Meanwhile, representative compounds could reduce tumor cell viability and the extracellular acidification in HT-29 and MDA-MB-231 cancer cell lines. Even more interestingly, our target compounds had no apparent cytotoxicity toward MCF-10A cell line. In addition, the in vitro stability assays also indicated our developed compounds possessed good liver microsomal metabolic stabilities and plasma stability. Furthermore, representative compounds revealed relatively low hERG cardiac toxicity and acute toxicity. Furthermore, docking studies were carried out to understand the interactions of our target compounds with the protein target CA IX. Collectively, our results suggest that compound 10a, as a selective CA IX inhibitor, could be an important lead compound for further optimization and development as an anticancer agent.

Newly synthesized bis-benzimidazole compound 8 induces apoptosis, autophagy and reactive oxygen species generation in HeLa cells.

Compound 8 (C8) is a newly synthesized bis-benzimidazole derivative and exerts significant anti-tumor activity in vitro. Previous studies demonstrated that C8 induced apoptosis and autophagy in human promyelocytic leukemia HL60 cells. However, cytotoxicity study on human peripheral blood mononuclear cells (hPBMC) showed that C8 exhibited less toxicity in normal cells. In this study, the molecular mechanism of C8 on human cervical carcinoma HeLa cells was investigated. The results showed that C8 inhibited the growth of HeLa cells and triggered both apoptotic and autophagic cell death. Subsequent experiment also indicated that reactive oxygen species (ROS) generation was induced in C8-treated HeLa cells. Since ROS scavenger decreased the ratio of apoptotic and autophagic cells, ROS generation contributed to C8-induced apoptosis and autophagy. Furthermore, inhibitors of apoptosis and autophagy also reduced ROS generation, respectively. Autophagy inhibition increased cell growth compared to C8-treated group and attenuated apoptotic cell death, indicating that C8-induced autophagy promoted apoptosis for cell death. However, the percentage of autophagic cells was enhanced when limiting apoptosis process. Taken together, C8 induced ROS-mediated apoptosis and autophagy in HeLa cells, autophagy promoted apoptosis but the former was antagonized by the latter. The data also gave us a new perspective on the anti-tumor effect of C8.

Newly synthesized bis-benzimidazole derivatives exerting anti-tumor activity through induction of apoptosis and autophagy.

In this study, a new series of bis-benzimidazole derivatives were designed and synthesized. Most of these new compounds showed significant anti-tumor activity in vitro compared to Hoechst 33258. Among them, the most potent compound 8 had the IC(50) values of 0.56µM for HL60 (Human promyelocytic leukemia cells) tumor cell line and 0.58µM for U937 (Human leukemic monocyte lymphoma cells) tumor cell line. Subsequent toxicity study on human peripheral blood mononuclear cells (PBMC) showed that compound 8 exhibited less toxicity than 5-FU. We also found that apoptosis and autophagy were simultaneously induced by compound 8 in HL60 cells, and inhibition of autophagy by 3-MA decreased compound 8-induced apoptosis, indicating that they acted in synergy to exert tumor cell death.

Cathelicidin-BF attenuate kidney injury through inhibiting oxidative stress, inflammation and fibrosis in streptozotocin-induced diabetic rats.

OBJECTIVE: To investigate protective efficacies and mechanisms of Cathelicidin-BF (BF-30) peptide on streptozotocin (STZ)-induced diabetic kidney injury. METHODS: Effects of BF-30 on hydrogen peroxide induced oxidative damage in HK-2 renal cells were assessed by CCK-8 method. Forty STZ-induced diabetic rats with kidney injury were randomly divided into model control group, BF-30 group at different doses (0.1, 0.3 and 0.9 mg/kg). Blood biochemical and kidney related indexes as well adrenal morphological changes, inflammation related markers of diabetic rats were measured. RESULTS: Cell viability of HK-2 cells with oxidative damage induced by hydrogen peroxide were significantly improved by BF-30 with 0.8 µg/mL for 56.5% and 1.6 µg/mL for 82.3% compared with control. Moreover, the decreased reactive oxygen species (ROS), and increased intracellular antioxidant enzymes GPX1, SOD2 and GSH were showed in BF-30 treated groups. In addition, co-incubation of BF-30 in HK-2 cells promoted the increase of p-AMPK and LC3, decreased activation of p-mTOR, BAX and Caspase 3. Chronic treatment of BF-30 improved the STZ-induced diabetic characteristics of diabetic kidney disease (DKD) model rats. Further renal histopathological examination revealed 12-week treatment of BF-30 effectively improved the morphology of nephropathy in DKD rats. Moreover, BF-30 also could ameliorate excessive oxidative stress, renal cell apoptosis and fibrosis, thereby protects renal tissues. CONCLUSION: BF-30 exerted protective effects on STZ-induced kidney injury mainly through the inhibiting oxidative stress in kidney tissue, reducing renal fibrosis, increasing autophagy, and reducing the renal cell apoptosis related proteins to decrease the cell damage and protect nephrocytes.